STRUCTURE AND SPECTRAL EVALUATION OF COVALENCY IN ND(III) TETRAKIS COMPLEXES WITH CARBACYLAMIDOPHOSPHATE LIGANDS
Two neodymium(III) tetrakis complexes with different carbacylamidophosphate ligands and a tetraethylammonium cation of the formulas NEt4[NdL14] (1Nd) and NEt4[NdL24]·iPrOH (2Nd) were synthesized, where [L1]⁻ is dimethyl-N-trichloroacetylamidophosphate, Cl3CC(O)NP(O)(OCH3)2⁻, and [L2]⁻ is diphenyl...
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V.I.Vernadsky Institute of General and Inorganic Chemistry
2025
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Репозитарії
Ukrainian Chemistry Journal| _version_ | 1871466183220264960 |
|---|---|
| author | Struhatska, Mariia Kariaka, Nataliia Trush, Viktor Dyakonenko, Viktoriya Shishkina, Svitlana Smola, Sergii Rusakova, Nataliia Amirkhanov, Volodymyr |
| author_facet | Struhatska, Mariia Kariaka, Nataliia Trush, Viktor Dyakonenko, Viktoriya Shishkina, Svitlana Smola, Sergii Rusakova, Nataliia Amirkhanov, Volodymyr |
| author_institution_txt_mv | [
{
"author": "Mariia Struhatska",
"institution": "Faculty of Chemistry, Taras Shevchenko National University of Kyiv"
},
{
"author": "Nataliia Kariaka",
"institution": "Faculty of Chemistry, Taras Shevchenko National University of Kyiv"
},
{
"author": "Viktor Trush",
"institution": "Faculty of Chemistry, Taras Shevchenko National University of Kyiv"
},
{
"author": "Viktoriya Dyakonenko",
"institution": "SSI “Institute for Single Crystals”, National Academy of Science of Ukraine"
},
{
"author": "Svitlana Shishkina",
"institution": "SSI “Institute for Single Crystals”, National Academy of Science of Ukraine; Institute of Organic Chemistry of the National Academy of Sciences of Ukraine"
},
{
"author": "Sergii Smola",
"institution": "A.V. Bogatsky Physicochemical Institute of the National Academy of Sciences of Ukraine"
},
{
"author": "Nataliia Rusakova",
"institution": "A.V. Bogatsky Physicochemical Institute of the National Academy of Sciences of Ukraine"
},
{
"author": "Volodymyr Amirkhanov",
"institution": "Faculty of Chemistry, Taras Shevchenko National University of Kyiv"
}
] |
| author_sort | Struhatska, Mariia |
| baseUrl_str | https://ucj.org.ua/index.php/journal/oai |
| collection | OJS |
| datestamp_date | 2026-07-22T08:23:56Z |
| description | Two neodymium(III) tetrakis complexes with different carbacylamidophosphate ligands and a tetraethylammonium cation of the formulas NEt4[NdL14] (1Nd) and NEt4[NdL24]·iPrOH (2Nd) were synthesized, where [L1]⁻ is dimethyl-N-trichloroacetylamidophosphate, Cl3CC(O)NP(O)(OCH3)2⁻, and [L2]⁻ is diphenyl-N-trichloroacetylamidophosphate, Cl3CC(O)NP(O)(OC6H5)2⁻. The compounds were characterized by elemental analysis, infrared spectroscopy, diffuse reflectance electronic spectroscopy, and single-crystal X-ray diffraction analysis. Structural analysis confirmed the formation of anionic complexes featuring a NdO8 coordination environment. Coordination polyhedra of central ions are best described as a triangular dodecahedron for 1Nd and a square antiprism for 2Nd. Diffuse reflectance spectra in the UV–vis–NIR region revealed characteristic f–f transitions of NdIII, with ligand-dependent modulation of band shape and intensity of the “hypersensitive” transitions. The bonding between the metal and the ligands was found to have weak covalent character. Luminescence studies of the 2Nd complex revealed weak emission sensitization by the ligands. |
| doi_str_mv | 10.33609/2708-129X.91.11.2025.3-21 |
| first_indexed | 2026-03-12T15:49:41Z |
| format | Article |
| fulltext |
3
UDC 546.3+543.4+539.26 doi: 10.33609/2708-129X.91.11.2025.3-21
STRUCTURE AND SPECTRAL EVALUATION
OF COVALENCY IN ND(III) TETRAKIS COMPLEXES
WITH CARBACYLAMIDOPHOSPHATE LIGANDS.
Mariia B. Struhatskaa,*, Nataliia S. Kariakaa, Viktor O. Trusha, Viktoriya V. Dyakonenkob,
Svitlana V. Shishkinac, Sergii S. Smolad, Nataliia V. Rusakovad, Volodymyr M. Amirkhanova
a Faculty of Chemistry, Taras Shevchenko National University of Kyiv,
12 Hetman Pavlo Skoropadsky Str., 01033 Kyiv, Ukraine;
b SSI “Institute for Single Crystals”, National Academy of Science of Ukraine,
60 Nauky ave., 61072 Kharkiv, Ukraine;
c Institute of Organic Chemistry of the National Academy of Sciences of Ukraine,
5 Akademika Kukharya Str., 02660 Kyiv, Ukraine;
d A.V. Bogatsky Physicochemical Institute of the National Academy of Sciences of Ukraine,
86 Lustdorfska doroga Str, 65080 Odessa, Ukraine
*e-mail: mariia.struhatska@knu.ua
Two neodymium(III) tetrakis complexes with different carbacylamidophosphate
ligands and a tetraethylammonium cation of the formulas NEt4[NdL1
4] (1Nd) and
NEt4[NdL2
4]·iPrOH (2Nd) were synthesized, where [L1]⁻ is dimethyl-N-trichloroacetyl
amidophosphate, Cl3CC(O)NP(O)(OCH3)2⁻, and [L2]⁻ is diphenyl-N-trichloroacetylami
dophosphate, Cl3CC(O)NP(O)(OC6H5)2⁻. The compounds were characterized by ele-
mental analysis, infrared spectroscopy, diffuse reflectance electronic spectroscopy, and
single-crystal X-ray diffraction analysis. Structural analysis confirmed the formation of
anionic complexes featuring a NdO8 coordination environment. Coordination polyhedra
of central ions are best described as a triangular dodecahedron for 1Nd and a square anti-
prism for 2Nd. Diffuse reflectance spectra in the UV–vis–NIR region revealed characteris-
tic f–f transitions of NdIII, with ligand-dependent modulation of band shape and intensity
of the “hypersensitive” transitions. The bonding between the metal and the ligands was
found to have weak covalent character. Luminescence studies of the 2Nd complex revealed
weak emission sensitization by the ligands.
Keywords: NdIII, carbacylamidophosphate, tetrakis complex, tetraethylammonium
cation, electronic spectroscopy, crystal structure.
4 ISSN 2708-129X. Укр. хім. журн., 2025
STRUCTURE AND SPECTRAL EVALUATION OF COVALENCY IN ND(III) TETRAKIS COMPLEXES
WITH CARBACYLAMIDOPHOSPHATE LIGANDS.INORGANIC CHEMISTRY
INTRODUCTION.
Lanthanide complexes with organic ligands
have emerged as key materials in a wide range
of high-tech applications, owing to the unique
photophysical, magnetic, and catalytic pro
perties imparted by their 4f electronic configu
ration [1, 2, 3]. Their sharp emission bands,
large excitation–emission energy difference,
and long excited-state lifetimes make these
complexes promising candidates for lumines-
cent devices such as organic light-emitting
diodes (OLEDs) [4, 5]. In molecular sensing,
lanthanide complexes act as selective probes
for detecting molecules, ions, or environmen-
tal changes, due to their environment-sensitive
emission[6, 7]. In the biomedical field, lan-
thanides are used in bioimaging and diagnos-
tic agents, where deep tissue penetration and
minimal autofluorescence are critical [8, 9].
Other applications of lanthanide(III) complex-
es with organic ligands include single-molecule
magnets [10, 11, 12, 13], structural damage
and pressure sensors [14, 15, 16, 17], polyme
ric optical waveguides and amplifiers [18, 19,
20], security inks [21, 22, 23], luminescent
thermometers [24, 25, 26, 27], solar concentra-
tors [28, 29], and catalysis [30, 31].
A structurally appealing subclass of coor-
dination compounds is represented by tetrakis
complexes, in which four acido-ligands sur-
round the metal center, typically resulting in
discrete anionic units balanced by organic or
inorganic counterions [32]. In the case of lan-
thanides, such tetrakis complexes offer several
advantages: high stability, predictable geomet
ry, and elimination of lanthanide lumines-
cence quenching due to saturation of the me
tal’s coordination sites – particularly crucial for
NIR-emitting lanthanide ions.
Among the various ligand systems emp
loyed for lanthanide complexation [33], car
bacylamidophosphates (CAPhs) represent a
versatile and promising class. Bidentate CAPh
ligands offer phosphoryl and carbonyl oxygen
donor atoms, capable of forming air-stable
chelates with lanthanide ions. The modular na-
ture of the CAPh framework allows fine-tun-
ing of the photophysical properties of their
metal complexes through substitution at the
carbon or phosphorus atoms. Moreover, CAPh
ligands tend to form rigid complexes with fa-
vorable solubility and crystallization behavior
and, with suitable substituents and triplet-state
energy, they may act as “antennas” and effi-
ciently sensitize LnIII luminescence [32, 34, 35].
Electronic spectroscopy is a valuable tool
for characterizing lanthanide complexes,
which, unlike transition metal complexes, of-
ten display sharp and well-defined electronic
transitions due to the shielding of f-electrons
within the inner orbitals of the lanthanide ions.
Each lanthanide ion exhibits characteristic ab-
sorption bands that can provide insight into
the coordination environment surrounding
the metal ion. Changes in ligand field strength
or coordination number may lead to shifts in
some of the absorption bands or variations in
their intensity [36]. The most commonly studi
ed lanthanide ions in electronic spectroscopy
include PrIII, NdIII, HoIII, and ErIII, due to the
relatively high intensity of their absorption
bands [37].
The absorption bands of neodymium(III)
in the visible and near-infrared regions arise
from intra-4f transitions from the ground state
4I9/2, which are Laporte-forbidden but become
partially allowed due to mixing of the 4f and
5d orbitals via the ligand field [38]. In NdIII
complexes, these bands typically exhibit a ba
5https://ucj.org.ua
Mariia B. Struhatska, Nataliia S. Kariaka, Viktor O. Trush, Viktoriya V. Dyakonenko, Svitlana V. Shishkina,
Sergii S. Smola, Nataliia V. Rusakova, Volodymyr M. Amirkhanov UCJ № 11 / Vol. 91
thochromic shift compared to the aqua ion,
known as the nephelauxetic shift [39, 40, 41,
42]. The nephelauxetic effect is related to the
degree of covalency in the metal-ligand bond
within the complex compared to the metal salt
in aqueous solution; stronger covalency leads
to a larger nephelauxetic shift. The degree of
the nephelauxetic shift has been found to de-
pend on the central ion’s coordination number
[43] and is therefore related to the metal–li-
gand distance [44]. The polarizability of the
ligand also affects the nephelauxetic shift [42].
The multiplicity of the 2P1/2 ← 4I9/2 transition
band, observed around 430 nm, can be used
to determine the number of optical centers in
a complex and thereby infer the structural in-
dividuality of the compound. In the absence of
a magnetic field, this transition is degenerate
and unaffected by the symmetry field, making
its splitting a valuable diagnostic parameter.
The so-called “hypersensitive” transition 4G5/2,
2G7/2 ← 4I9/2 near 580–600 nm is responsive to
ligand field effects and coordination geome-
try [45]. Complexation results in a pronounced
increase in the intensities of the components of
this transition band. The band profile has also
been utilized as a diagnostic tool for determin-
ing the coordination number of the central
metal ion [45, 46], including in complexes with
CAPh ligands [47, 48, 53].
In this work, we report the synthesis and
comprehensive characterization of two NdIII
tetrakis complexes with two types of CAPh li
gands, with the formulas NEt4[NdL1
4] (1Nd) and
NEt4[NdL2
4]·iPrOH (2Nd), where [L1]⁻ is de-
protonated dimethyl-N-trichloroacetylamido
phosphate, Cl3CC(O)NP(O)(OCH3)2⁻, and
[L2]⁻ is diphenyl-N-trichloroacetylamidophos
phate-anion, Cl3CC(O)NP(O)(OC6H5)2⁻. Gra
phical formulas of the ligands are shown in
Figure 1. The compounds were characterized
using elemental analysis, single-crystal X-ray
diffraction, infrared, and diffuse reflectance
electronic spectroscopy. The luminescence
properties of the 2Nd were also studied. The
work aims to evaluate how variations in ligand
structure influence the coordination geometry,
Nd–O bonds covalency, and spectral proper-
ties of the NdIII ion in the solid state.
Fig. 1. Graphical formulas of HL1 (a) and HL2 (b).
EXPERIMENT AND DISCUSSION OF THE
RESULTS.
Materials and methods.
All reagents were obtained from commer-
cial sources and used without further purifica-
tion. Solvents used in the syntheses were dried
using standard literature procedures.
Elemental analysis was performed using
a CHNS Vario EL Cube Elemental Analyzer.
The lanthanide content in the complexes was
6 ISSN 2708-129X. Укр. хім. журн., 2025
STRUCTURE AND SPECTRAL EVALUATION OF COVALENCY IN ND(III) TETRAKIS COMPLEXES
WITH CARBACYLAMIDOPHOSPHATE LIGANDS.INORGANIC CHEMISTRY
determined by standard titrimetric methods
for lanthanide ions [49].
Single-crystal X-ray diffraction data for
structure 1Nd were collected at 294 K using
an Xcalibur Sapphire3 diffractometer, and for
structure 2Nd at 296 K using a Bruker APEX-
II CCD diffractometer, both equipped with
graphite-monochromated MoKa radiation
(λ = 0.71073 Å). Using Olex2 software [50], the
structures were solved with the SHELXT [51]
program using Intrinsic Phasing and refined
with the SHELXL [52] refinement package.
Full-matrix least-squares refinement against
F2 in anisotropic approximation was used for
non-hydrogen atoms. Positions of the hydro-
gen atoms were located from electron density
difference maps and refined by “riding” model
with Uiso = nUeq of the carrier atom
(n = 1.5 for methyl and hydroxyl groups and
n = 1.2 for other hydrogen atoms). Crystal data
and refinement parameters are summarized in
Table 1.
Infrared (IR) spectra were recorded on a
Perkin Elmer Spectrum BX spectrometer us-
ing KBr pellets in the range of 400–4000 cm⁻1.
Diffuse reflectance electronic spectra of
solid 1Nd and 2Nd were measured with a Shi-
madzu UV-2600і spectrometer.
Emission and excitation spectra of 2Nd
were measured on a “Fluorolog FL 3-22” spec-
trofluorometer at 298 K.
Synthesis.
The ligands HL1 and HL2, as well as their so
dium salts, were synthesized according to pre
viously described procedures [34, 53, 54].
The LnIII complexes were obtained accor
ding to the following schemes:
Nd(NO3)3∙6H2O + 4NaL1 + NEt4Cl =
= NEt4[NdL1
4] + 3NaNO3 + NaCl + 6H2O,
Nd(NO3)3∙6H2O + 4NaL2 + NEt4Cl + iPrOH =
= NEt4[NdL2
4]·iPrOH + 3NaNO3 + NaCl + 6H2O.
The hydrated neodymium(III) nitrate
(1 mmol, 0.43835 g) was dissolved in acetone
(10 mL) under heating for one minute. Next,
the dehydrating reagent, triethyl orthoformate
(6 mmol, 1 ml), was added, and the resulting
solution was boiled for 1 min. Separately, NaL1
(4 mmol, 1.1696 g) or NaL2 (4 mmol, 1.6664 g)
was dissolved in acetone (10 mL) under heat-
ing. Additionally, tetraethylammonium chlo-
ride (1 mmol) was dissolved in 2-propanol
(5 mL) under heating. The three prepared solu-
tions were combined and refluxed for 10 min.
The resulting solution was cooled to room
temperature for 10 min, and the precipitated
NaNO3 was filtered off. After 1 - 2 days, the
target complexes began to crystallize from the
filtrate. The compounds were separated from
the mother liquor, washed with 2-propanol,
and dried in air. The average yields of products
1Nd and 2Nd were 55 and 78 %, respectively.
The obtained complexes were stable in air, well
soluble in methanol, acetone, dimethylfor-
mamide (DMF), dimethyl sulfoxide (DMSO),
acetonitrile, ethyl acetate, 1,4-dioxane, dichlo-
romethane, chloroform, and in 2-propanol
(upon heating). The compounds were inso
luble in tetrachloromethane, benzene, hexane,
and water.
NEt4[NdL1
4] (1Nd) Yield: 55 %. M.p.:
157 °C. Anal. Calcd for C24H44Cl12N5NdO16P4
(Mr = 1352.20) (%): Nd, 10.67; C, 21.32; H,
3.28; N 5.18. Found, %: Nd, 11.3; C, 21.14;
H, 3.25; N, 5.32. IR (KBr): νmax = 2992 (w),
2952 (m), 2850 (w), 1620 (vs), 1484 (m),
1462 (w), 1456 (w), 1442 (w, sh), 1393 (w), 1366
(vs), 1186 (s), 1164 (vs), 1046 (vs), 1012 (s),
882 (vs), 845 (s), 836 (s), 820 (s), 780 (m), 726
(m), 674 (m), 548 (s), 498 (m), 460 (m) cm−1.
7https://ucj.org.ua
Mariia B. Struhatska, Nataliia S. Kariaka, Viktor O. Trush, Viktoriya V. Dyakonenko, Svitlana V. Shishkina,
Sergii S. Smola, Nataliia V. Rusakova, Volodymyr M. Amirkhanov UCJ № 11 / Vol. 91
NEt4[NdL2
4]·iPrOH (2Nd) Yield: 78 %. M.p.:
225 °C. Anal. Calcd for C67H68Cl12N5NdO17P4
(Mr = 1908.85) (%): Nd, 7.6; C, 42.16; H, 3.59;
N 3.67. Found, %: Nd, 8.1; C, 41.67; H, 3.49; N,
3.81. IR (KBr): νmax = 3070 (w), 2924 (m), 2854
(w), 1618 (vs), 1588 (vs), 1490 (vs), 1455 (m),
1440 (w), 1393 (m, sh), 1370 (vs), 1288 (w),
1218 (s), 1192 (vs), 1180 (vs, sh), 1166 (vs),
1072 (w), 1020 (s), 1005 (s, sh), 948 (vs, sh),
939 (vs), 908 (m), 876 (s), 820 (s), 776 (s), 761
(s), 718 (w), 690 (s), 677 (s), 615 (w), 590 (m),
574 (w), 526 (s), 504 (m), 462 (w, sh) cm−1.
X-ray Crystal Structure.
The 1Nd and 2Nd complexes crystallize
in the monoclinic crystal system in space
groups P21/c and C2/c, respectively. The crys-
tallographic data for the compounds are listed
in Table 1. The asymmetric unit cell of 1Nd
and eight of 2Nd complexes contains one
anion [NdL1/L2
4]⁻ ([L1]⁻ is a deprotonated
dimethyl-N-trichloroacetylamidophosphate,
Cl3CC(O)NP(O)(OCH3)2⁻, and [L2]⁻ is diphe-
nyl-N-trichloroacetylamidophosphate-anion,
Cl3CC(O)NP(O)(OC6H5)2⁻) and one cation
NEt4
+. The 2Nd complex crystallizes as sol-
vate with isopropanol. Deprotonated CAPh
ligands coordinate to the lanthanide ions in
a bidentate chelating mode via the oxygen
atoms of phosphoryl and carbonyl groups,
forming six-membered metallacycles (Fi
gure 2). The coordination polyhedra of the
lanthanide ions were determined using the
SHAPE 2.1 software [55] as a triangular do-
decahedron for 1Nd and a square antiprism
for 2Nd (Table 2, Figure 3). Compared with
the free ligand HL1 and sodium salt NaL2
[56], the average bond lengths of P—O and
C—O in the 1Nd and 2Nd complexes are
elongated, while the P—N and C—N bonds
are shortened, which is consistent with coor-
dination-induced π-delocalization. The aver-
age Ln—O(P) bond lengths are shorter than
the Ln—O(C) ones, which is attributed to
the stronger affinity of the phosphoryl group
for lanthanide ions. However, replacement
of substituents from OMe to OPh leads to an
elongation of Ln—O(P) bonds and a shor
tening of Nd—O(C) bonds in 2Nd compared
with 1Nd. The Nd—O(P) and Nd—O(C)
distances vary within 2.374(7)–2.395(8) Å
and 2.492(8)–2.499(9) Å, respectively, for
complex 1Nd, and 2.391(7)–2.425(7) Å and
2.432(6)–2.472(7) Å for complex 2Nd. All the
Nd—O bonds are shorter than the sum of the
van der Waals radii of oxygen and the Nd3+
ionic radius (2.61 Å). The average length of
Nd—O bonds in 2Nd (2.43363 Å) is slight-
ly smaller than in 1Nd (2.43725 Å). The
O—Nd—O bond angles vary from 72.0(3)° to
74.7(3)° for 1Nd and from 71.6(3)° to 73.5(3)°
for 2Nd (Table 3). The values of the distanc-
es and angles are in good agreement with the
data obtained for NdIII complexes with CAPhs
[57, 58].
As a result of the coordination of Nd atoms
by organic ligands in structures 1Nd and 2Nd,
the six-membered metallacycles are formed.
The metallacycles in the 1Nd and 2Nd struc-
tures are either planar or adopt sofa- or boat-
like conformations. The geometric characteris-
tics of the conformations of the six-membered
metallacycles are presented in Table 4.
In the crystal phase, the molecules of the
anion and cation (in 1Nd), as well as the ani-
on, cation, and solvent molecules (in 2Nd), are
linked by numerous intermolecular interac-
tions, forming a three-dimensional molecular
packing network.
8 ISSN 2708-129X. Укр. хім. журн., 2025
STRUCTURE AND SPECTRAL EVALUATION OF COVALENCY IN ND(III) TETRAKIS COMPLEXES
WITH CARBACYLAMIDOPHOSPHATE LIGANDS.INORGANIC CHEMISTRY
Table 1.
Crystal data and structure refinement parameters for 1Nd and 2Nd.
Parameter 1Nd 2Nd
formula C24H44Cl12N5NdO16P4 C67H48Cl12N5NdO17P4
M 1352.16 1887.62
T [K] 294 296.15
crystal system monoclinic monoclinic
space group P21/c C2/c
a [Å] 20.5200(11) 25.610(3)
b [Å] 12.3252(6) 15.281(3)
c [Å] 21.4083(11) 42.846(6)
α [°] 90 90
β [°] 92.577(4) 97.330(13)
γ [°] 90 90
V [Å3] 5409.0(5) 16631(4)
Z 4 8
Dc [mg cm-3] 1.660 1.509
μ [mm-1] 1.730 1.151
F(000) 2700 7560
crystal size [mm] 0.2 x 0.4 x 0.5 0.1 x 0.2 x 0.3
reflections collected 38576 71669
independent reflections (Rint) 10616 14544
data/parameters 10616 / 624 14544 / 990
GOF 0.999 1.125
R1 [I>2σ(I)] 0.098 0.1045
wR2 [I>2σ(I)] 0.2422 0.1970
R1 [all data] 0.1698 0.1572
wR2 [all data] 0.2883 0.2140
CCDC 2486751 2486752
Table 2.
Continuous Shape Measures (CShMs) of the coordination geometry for 1Nd and 2Nd
crystal structures.
Label Symmetry Shape 1Nd 2Nd
OP-8 D8h Octagon 31.986 28.250
HPY-8 C7v Heptagonal pyramid 23.995 23.297
HBPY-8 D6h Hexagonal bipyramid 16.557 16.220
CU-8 Oh Cube 10.324 8.961
9https://ucj.org.ua
Mariia B. Struhatska, Nataliia S. Kariaka, Viktor O. Trush, Viktoriya V. Dyakonenko, Svitlana V. Shishkina,
Sergii S. Smola, Nataliia V. Rusakova, Volodymyr M. Amirkhanov UCJ № 11 / Vol. 91
Label Symmetry Shape 1Nd 2Nd
SAPR-8 D4d Square antiprism 1.938 0.221
TDD-8 D2d Triangular dodecahedron 0.450 2.206
JGBF-8 D2d Johnson gyrobifastigium J26 13.036 16.327
JETBPY-8 D3h Johnson elongated triangular bipyramid J14 28.648 28.275
JBTPR-8 C2v Biaugmented trigonal prism J50 2.311 2.934
BTPR-8 C2v Biaugmented trigonal prism 2.016 2.140
JSD-8 D2d Snub diphenoid J84 2.205 5.191
TT-8 Td Triakis tetrahedron 10.878 9.779
ETBPY-8 D3h Elongated trigonal bipyramid 25.123 23.577
1Nd 2Nd
Fig. 2. The molecular structures of the [NdL1/L2
4]
– anions in 1Nd and 2Nd (H atoms are omitted
for clarity). Thermal ellipsoids are shown at 50 % probability level.
1Nd 2Nd
Fig. 3. Coordination polyhedra of the NdIII ions in 1Nd and 2Nd.
Table 2.
10 ISSN 2708-129X. Укр. хім. журн., 2025
STRUCTURE AND SPECTRAL EVALUATION OF COVALENCY IN ND(III) TETRAKIS COMPLEXES
WITH CARBACYLAMIDOPHOSPHATE LIGANDS.INORGANIC CHEMISTRY
Table 3.
Selected bond lengths [Å] and angles [º] in 1Nd and 2Nd complexes.
1Nd 2Nd
Nd1—O1 2.395 (8) Nd1—O1 2.436 (7)
Nd1—O4 2.499 (9) Nd1—O4 2.391 (7)
Nd1—O5 2.374 (7) Nd1—O5 2.465 (7)
Nd1—O8 2.482 (7) Nd1—O8 2.425 (7)
Nd1—O9 2.378 (7) Nd1—O9 2.472 (7)
Nd1—O12 2.493 (9) Nd1—O12 2.432 (7)
Nd1—O13 2.385 (7) Nd1—O14 2.443 (7)
Nd1—O16 2.492 (8) Nd1—O17 2.405 (6)
P1—O1 1.478 (9) P1—O4 1.486 (7)
P1—N1 1.589 (13) P1—N1 1.613 (9)
P2—O5 1.491 (8) P2—O8 1.482 (7)
P2—N2 1.590 (11) P2—N2 1.600 (9)
P3—O9 1.479 (8) P3—O12 1.440 (7)
P3—N3 1.563 (13) P3—N3 1.608 (10)
P4—O13 1.475 (8) P4—O17 1.478 (7)
P4—N4 1.564 (11) P4—N4 1.590 (8)
O4—C3 1.279 (14) O1—C1 1.227 (11)
O8—C7 1.221 (13) O5—C15 1.240 (12)
O12—C11 1.27 (2) O9—C29 1.216 (12)
O16—C15 1.231 (16) O14—C43 1.273 (12)
N1—C3 1.280 (17) N1—C1 1.286 (13)
N2—C7 1.355 (16) N2—C15 1.286 (13)
N3—C11 1.27 (2) N3—C29 1.298 (14)
N4—C15 1.312 (17) N4—C43 1.286 (13)
O1—Nd1—O4 72.6 (3) O1—Nd1—O4 71.6 (2)
O5—Nd1—O8 74.7 (3) O5—Nd1—O8 71.8 (2)
O9—Nd1—O12 72.7 (3) O9—Nd1—O12 72.0 (2)
O13—Nd1—O16 73.3 (3) O14—Nd1—O17 73.5 (2)
Table 4.
The conformational characteristics of six-membered metallocycles in 1Nd and 2Nd.
Cycle Mean plane atoms, rmsd/Å Deviation of
atom, Å
Type of
conformation
1Nd
Nd1–O1–P1–N1–C3–O4 Nd1…O1…N1…C3 0.01 O4 -0.21(3)
P1 -0.21(4)
boat
Nd1–O5–P2–N2–C7–O8 Nd1…O8…C7…N2…O5 0.02 P2 -0.27(4) sofa
Nd1–O9–P3–N3–C11–O12 Nd1…O9…P3…N3…C11…O12 0.03 – planar
Nd1–O13–P4–N4–C15–O16 O13…P4…N4…C15…O16 0.03 Nd1 0.45(4) sofa
2Nd
Nd1–O4–P1–N1–C1–O1 O4…P1…N1…C1…O1 0.01 Nd1 0.53(4) sofa
Nd1–O8–P2–N2–C15–O5 Nd1…O8…P2…N2…C15…O5 0.03 – planar
Nd1–O12–P3–N3–C29–O9 O12…P3…N3…C29…O9 0.02 Nd1 -0.46(5) sofa
Nd1–O17–P4–N4–C4–O14 Nd1…O17…P4…N4…C4…O14 0.03 – planar
11https://ucj.org.ua
Mariia B. Struhatska, Nataliia S. Kariaka, Viktor O. Trush, Viktoriya V. Dyakonenko, Svitlana V. Shishkina,
Sergii S. Smola, Nataliia V. Rusakova, Volodymyr M. Amirkhanov UCJ № 11 / Vol. 91
Infrared spectroscopy
The IR spectra of the 1Nd and 2Nd comp
lexes, recorded as KBr pellets in the range
of 4000–400 cm−1 (Figure 4), confirm the
successful coordination of the deprotona
ted CAPh ligands to the NdIII ions and the
presence of tetraethylammonium counte-
rions. The absence of a broad band around
3080 cm−1, which would correspond to the
ν(H—N) stretching vibration, indicates that
the ligands in the obtained complexes exist in
their acidic form. In the high-frequency re-
gion, a weak-intensity band at 3070 cm−1 cor-
responds to the C—H stretching vibrations of
the phenyl rings in the (L2)⁻ ligand of 2Nd,
while medium- and weak-intensity bands in
the region 2992–2850 cm−1 are assigned to the
asymmetric and symmetric C—H stretching
vibrations of the methyl groups in (L1)⁻ (1Nd)
and of the methyl and methylene groups in
the counterions of both complexes. A strong
band at 1620 - 1618 cm−1 is assigned to the
ν(C=O) stretching vibration of the coordi-
nated carbonyl group. Compared to the free
ligands HL1 [56] and HL2 [53], this band is
shifted to lower wavenumbers in the IR spec-
tra of the complexes, indicating coordination
of the C=O group to the NdIII ions through
the carbonyl oxygen atom. The aromatic ring
skeletal vibrations, involving carbon–carbon
stretching, in the spectrum of 2Nd appear at
1588 and 1490 cm−1. The asymmetric bend-
ing vibration 𝛿as(CH3) from the NEt4⁺ coun-
terion, as well as from the HL1 framework,
appears at 1455 cm−1, while the symmetric
bending vibration 𝛿s(CH3) is observed at
1393 cm−1. The bending vibration 𝛿s(CH2) of
the methylene groups is located at 1462 cm−1.
Strong bands at 1366 cm−1 for 1Nd and at
1370 cm−1 for 2Nd are attributed to a mixed
vibration involving C—C and C—N stretch-
ing. The phosphoryl group exhibits several
distinct bands: the strong band in the region
1192–1186 cm−1 is assigned to the characte
ristic P=O stretching vibration of the CAPh
ligand, while the band at 1166–1164 cm−1 cor-
responds to a coupled P=O and P—N stretch-
ing mode. These bands are shifted to lower
wavenumbers in the spectra of the synthe-
sized complexes compared to the spectra of
the free ligands. Additional band in the region
1046–1020 cm−1 represents coupled stretch-
ing vibrations ν(PN)*ν(CC) of the ligands.
Another strong band at 1012 cm−1 in the 1Nd
and at 1020 cm−1 in the 2Nd spectra reflects
coupled P=O and P—N stretching vibration.
An aromatic C—H in-plane bending band
from the ligands in 2Nd appears at 948 and
1072 cm−1, while the out-of-plane bending is
reflected in the bands at 761 and 690 cm−1. The
CCl3 group can be identified by absorption
bands of an asymmetric stretching vibration
at 780–776 cm−1 and a symmetric stretch at
677–674 cm−1. A band at 726–718 cm−1 is attri
buted to chelate ring breathing ν(ϕ). A medi-
um-intensity absorption band that appears in
the spectrum of 2Nd at 590 cm−1 is attributed
to out-of-plane ring bending. A strong-in-
tensity band at 548 cm−1 (1Nd) and 526 cm−1
(2Nd) is assigned to a coupled deformation
involving in-plane chelate ring bending and
Nd—O stretching modes δ(ϕ)*ν(Nd—O).
Medium and weak bands at 504–498 and
462–460 cm−1 are assigned to the deformation
vibrations of the trichloromethyl group (δ(C-
Cl3)) and in-plane chelate ring bending (δ(ϕ))
of the ligands, respectively. The band assign-
ments were made according to references [59,
60, 61].
12 ISSN 2708-129X. Укр. хім. журн., 2025
STRUCTURE AND SPECTRAL EVALUATION OF COVALENCY IN ND(III) TETRAKIS COMPLEXES
WITH CARBACYLAMIDOPHOSPHATE LIGANDS.INORGANIC CHEMISTRY
Fig. 4. Mid-FTIR spectra of 1Nd and 2Nd complexes in the form of KBr pellets.
Electronic spectroscopy.
The electronic diffuse reflectance spectra
of powders of 1Nd and 2Nd complexes were
recorded in the 400–900 nm range at room
temperature and are shown in Figure 5. Both
spectra exhibit characteristic f–f transitions
of NdIII ions from the 4I9/2 ground state. The
absorption bands were assigned according to
reference [62]. The hypersensitive transition
band in the region near 58–600 nm (4G5/2,
2G7/2 ← 4I9/2) is similar to that observed in other
previously reported CAPh-based lanthanide
complexes with a coordination number of eight
for the central atom[63, 64, 0]. The relative in-
tensities of the components of this band vary
slightly between 1Nd and 2Nd due to diffe
rent coordination polyhedra of the central ions
(Table 2). The band of the 2P1/2 ← 4I9/2 transition,
with maxima at 430.4 and 429.2 nm for 1Nd
and 2Nd, respectively, shows no observable
splitting in either spectrum, indicating single
crystallographically equivalent NdIII centers
in both complexes, consistent with structural
data from X-ray diffraction. Electronic tran-
sitions from thermally populated higher sub
levels of the ground energy level result in the
appearance of relatively intense absorption
bands in the wavelength range of 432–436 nm.
13https://ucj.org.ua
Mariia B. Struhatska, Nataliia S. Kariaka, Viktor O. Trush, Viktoriya V. Dyakonenko, Svitlana V. Shishkina,
Sergii S. Smola, Nataliia V. Rusakova, Volodymyr M. Amirkhanov UCJ № 11 / Vol. 91
Fig. 5. Electronic diffuse reflection spectra (upper panel); 2P1/2 ← 4I9/2 and 2G7/2,
4G5/2 ← 4I9/2
transition bands (lower panel) of 1Nd and 2Nd at 300 K.
14 ISSN 2708-129X. Укр. хім. журн., 2025
STRUCTURE AND SPECTRAL EVALUATION OF COVALENCY IN ND(III) TETRAKIS COMPLEXES
WITH CARBACYLAMIDOPHOSPHATE LIGANDS.INORGANIC CHEMISTRY
To evaluate the extent of metal-ligand or-
bital mixing, the nephelauxetic parameter 11 /
n i i
c aqn
β ν ν
−
∑= , the covalency parameter
1 100%βδ
β
−
= , the bonding parameter
1/2 1
2
b β−
= and the angular overlap parameter
1 β
η
β
−
= were calculated by comparing the
shifts of the transition bands in the diffuse
reflectance spectra of the complexes ( i
cν ) with
respect to the positions of the corresponding
bands in the spectrum of the NdIII aquo-ion
( i
aqν ) (Tables 5, 6) [40, 62, 65]. The obtained
results are very similar for the 1Nd and 2Nd
complexes and suggest weak covalent bonding
between the NdIII ions and the ligands, which is
in agreement with data reported for other com-
plexes with CAPhs [47]. A slightly larger value of
δ for 2Nd is consistent with the slightly shorter
Nd—O bonds in this complex compared to 1Nd.
Table 5.
Positions of electronic transition spectral band maxima in diffuse reflection spectra of
an aquo-ion and 1Nd and 2Nd complexes [cm-1].
J-level Aquo-ion 1Nd 2Nd
4D1/2 28850 - 28694
4D5/2 28500 28498 28417
4D3/2 28300 28019 28019
2D5/2 23900 23759 -
2P1/2 23250 23234 23299
4G11/2 21650 21575 21575
2G9/2, (
2D, 2P)3/2 21300 21249 21281
2K15/2 21000 20964 20964
4G9/2 19550 19508 19535
4G7/2 19160 19073 19048
2G7/2 17460 17238 17232
4G5/2 17300 17150 17117
2H11/2 15870 15918 15949
4F9/2 14700 14596 14599
4F7/2,
2S3/2 13500 13335 13317
2H9/2 12590 12458 12469
4F5/2 12480 - 12392
4F3/2 11460 11443 11443
Table 6.
The nephelauxetic parameter β, the covalency parameter δ, the bonding parameter b1/2
and the angular overlap parameter η for 1Nd and 2Nd.
β δ [%] b1/2 η
1Nd 0.99498 0.50471 0.05011 0.00252
2Nd 0.99494 0.50863 0.05030 0.00254
15https://ucj.org.ua
Mariia B. Struhatska, Nataliia S. Kariaka, Viktor O. Trush, Viktoriya V. Dyakonenko, Svitlana V. Shishkina,
Sergii S. Smola, Nataliia V. Rusakova, Volodymyr M. Amirkhanov UCJ № 11 / Vol. 91
Luminescence spectroscopy
Considering the presence of aromatic sub-
stituents in the HL2, we undertook widespread
investigations of 2Nd for luminescence measu
rements. The HL2 ligand possesses a triplet ex-
cited state T1 located at 24270 cm-1 [54], which
lies significantly above the emissive 4F3/2 level
of Nd3+ (11698 cm-1). The energy gap between
the ligand triplet state and the NdIII emitting
level is therefore sufficiently large to allow li-
gand-to-metal energy transfer to occur in 2Nd.
However, the relatively high value of ΔE also
implies that additional non-radiative pathways
may compete with the sensitization process. In
particular, the excess energy gap can facilitate
back energy transfer and multiphonon relaxa
tion, which may partially quench the popula-
tion of the NdIII emissive state. Upon excita-
tion of 2Nd at 354 nm, the complex exhibits
typical f-f emission of the NdIII ion in the NIR
region, with narrow bands observed near 900,
1060 and 1330 nm (Figure 6, right panel). The
luminescence excitation spectrum of 2Nd,
recorded by monitoring NdIII f-f emission at
1060 nm, exhibits a number of narrow bands,
which were assigned to NdIII f-f transitions
from the ground 4I9/2 level (Figure 6, left pa
nel). The predominance of f-f transitions in the
excitation spectrum indicates inefficient sensi-
tization of NdIII emission by the ligands, which
is probably due to the large distance between
the lanthanide ion and the aromatic substitu-
ents in HL2 as well as due to the excess ener-
gy gap between the ligands’ lowest triplet state
and the emissive level of the neodymium ion,
which can facilitate energy dissipation. Earlier,
we have reported dimethyl-N-benzoylamido-
phosphate based complex NEt4NdL4 [66], in
which, despite of the big energy gap between
the ligand triplet state and the NdIII emitting
level an efficient sensitization of NdIII emission
was observed. This example underlines the im-
portance of the distance between the ligands’
chromophore and the lanthanide for efficiency
of the antenna effect.
Fig. 6. Luminescence excitation (left panel) and luminescence (right panel)
spectra of 2Nd at room temperature.
16 ISSN 2708-129X. Укр. хім. журн., 2025
STRUCTURE AND SPECTRAL EVALUATION OF COVALENCY IN ND(III) TETRAKIS COMPLEXES
WITH CARBACYLAMIDOPHOSPHATE LIGANDS.INORGANIC CHEMISTRY
CONCLUSIONS.
Two new neodymium(III) tetrakis comp
lexes with different carbacylamidophosphate
ligands were synthesized and structurally and
spectrally characterized.
Structural analysis revealed that variation in
the organic substituents on the CAPh ligands
results in distinct coordination polyhedra: a
triangular dodecahedron in complex 1Nd and
a square antiprism in 2Nd, both maintaining
an eight-coordinate NdO8 environment. The
substitution of OCH3 with OPh also causes
minor differences in metal–ligand distances;
however, confirmation of this conclusion re-
quires the investigation of a broader series of
related compounds.
Electronic diffuse reflectance spectra of the
complexes display well-resolved f–f transitions
of NdIII, including hypersensitive bands whose
shape depends on the ligand framework. The
absence of splitting in the 2P1/2 ← 4I9/2 transi-
tion indicates the presence of a single crystal-
lographically unique NdIII ion in each complex,
corroborating the crystallographic data. Co-
valency parameters (δ, b1/2, and η), calculated
based on nephelauxetic shifts (β) relative to the
NdIII aquo ion, indicate weak covalency in the
Nd–ligand bonding. The slightly higher δ va
lue observed for 2Nd compared to 1Nd is con-
sistent with shorter metal–ligand distances in
the structure of 2Nd.
Analysis of the excitation spectrum of 2Nd
showed that diphenyl-N-trichloroacetylami-
dophosphate in this complex insufficiently
sensitizes neodymium(III) emission, despite
the high enough energy of the ligand tri-
plet state relative to the NdIII emissive level,
which highlights the need for future ligand
designs that combine appropriate triplet-state
alignment with enhanced absorption and
improved suppression of nonradiative decay
channels.
This study demonstrates that the structural
variation in CAPh ligands enables fine-tuning
of both coordination geometry and electronic
spectral characteristics in lanthanide complex-
es. These findings support further exploration
of CAPh ligands for designing Nd-based ma-
terials with tailored spectral properties for po-
tential photonic and sensing applications.
ACKNOWLEDGEMENT. This work
was supported by Ministry of Edu-
cation and Science of Ukraine (grant
22BF037-04).
СТРУКТУРА ТА СПЕКТРАЛЬНА ОЦІНКА
КОВАЛЕНТНОСТІ У ТЕТРАКІС-КОМПЛЕКСАХ
ND(III) З КАРБАЦИЛАМІДОФОСФАТНИМИ
ЛІГАНДАМИ
М. Б. Стругацькаa,*, Н. С. Карякаa,
В. О. Трушa, В. В. Дьяконенкоб,
С. В. Шишкінав, С. С. Смолаг,
Н. В. Русаковаг, В. М. Амірхановa
a Хімічний факультет Київського нацiональ-
ного унiверситету iм. Тараса Шевченка,
вул. Гетьмана Павла Скоропадського, 12,
Київ 01033, Україна;
б Науково-технологічний комплекс “Інсти-
тут монокристалів” Національної академії
наук України, просп. Науки, 60, Харків 61072,
Україна;
в Інститут органічної хімії Національної
академії наук України,
вул. Академіка Кухаря, 5, Київ 02094, Україна;
г Фізико-хімічний інститут ім. О. В. Богат-
ського Національної академії наук України,
вул. Люстдорфська дорога, 86, Одеса 65080,
Україна
*e-mail: mariia.struhatska@knu.ua
17https://ucj.org.ua
Mariia B. Struhatska, Nataliia S. Kariaka, Viktor O. Trush, Viktoriya V. Dyakonenko, Svitlana V. Shishkina,
Sergii S. Smola, Nataliia V. Rusakova, Volodymyr M. Amirkhanov UCJ № 11 / Vol. 91
Синтезовано два тетракіс-комплек-
си неодиму(III) NEt4[NdL1
4] (1Nd) та
NEt4[NdL2
4]·iPrOH (2Nd) із тетраетиламо
нієвим катіоном та різними карбациламі
дофосфатними лігандами: [L1]⁻ – диметил-
N-трихлорацетиламідофосфат,
Cl3CC(O)NP(O)(OCH3)2⁻, та [L2]⁻ – дифеніл-
N-трихлорацетиламідофосфат,
Cl3CC(O)NP(O)(OC6H5)2⁻. Сполуки було
охарактеризовано за допомогою елемент-
ного аналізу, інфрачервоної спектроско-
пії, електронної спектроскопії дифузного
відбиття та рентгеноструктурного аналізу.
Методом РСтА встановлено утворення ані-
онних комплексів із координаційним ото-
ченням неодиму(ІІІ) NdO8. Координаційні
поліедри центральних йонів найкраще
описують як трикутний додекаедр у випад-
ку 1Nd і квадратна антипризма для 2Nd.
Спектри дифузного відбиття в УФ, види-
мій і ближній ІЧ-області демонструють f–f
переходи, характерні для NdIII, при цьому
форма та інтенсивність смуг надчутливих
переходів залежить від природи лігандів.
Було встановлено слабкий ковалентний ха-
рактер зв’язку метал – ліганд. Досліджен-
ня люмінесценції комплексу 2Nd виявили
слабку сенсибілізацію емісії лігандом.
Ключові слова: NdIII, карбациламідо-
фосфат, тетракіс-комплекс, тетраетиламо-
нієвий катіон, електронна спектроскопія,
кристалічна структура.
REFERENCES
1. Alexander C., Guo Z., Glover P.B., Faulkner S.,
Pikramenou Z. Luminescent lanthanides in bio
related applications: from molecules to nano-
particles and diagnostic probes to therapeutics.
Chemical Reviews. 2025. 125(4): 2269–2370.
https://doi.org/10.1021/acs.chemrev.4c00615
2. Binnemans K. Rare-earth beta-diketonates.
Handbook on the physics and chemistry of rare
earths. Elsevier. 2005. 35: 107–272.
https://doi.org/10.1016/S0168-1273(05)35
003-3
3. Singh A.K. Multifunctionality of lanthanide-
based luminescent hybrid materials. Coordi-
nation Chemistry Reviews. 2022. 455: 214365.
https://doi.org/10.1016/j.ccr.2021.214365
4. Bünzli J.C.G. Rising stars in science and tech-
nology: luminescent lanthanide materials. Eu-
ropean Journal of Inorganic Chemistry. 2017.
2017(44): 5058–5063.
https://doi.org/10.1002/ejic.201701201
5. de Bettencourt-Dias A. Lanthanide-based
emitting materials in light-emitting diodes.
Dalton Transactions. 2007. 22: 2229–2241.
https://doi.org/10.1039/B702341C
6. Sahoo J., Jaiswar S., Jena H.S., Subrama
nian P.S. Sensing of phosphate and ATP by
lanthanide complexes in aqueous medium and
its application on living cells. Chemistry Select.
2020. 5(42): 12878–12884.
https://doi.org/10.1002/slct.202002714
7. Bodman S.E., Butler S.J. Advances in anion
binding and sensing using luminescent lantha-
nide complexes. Chemical Science. 2021. 12(8):
2716–2734.
https://doi.org/10.1039/D0SC05419D
8. Wang M., Kitagawa Y., Hasegawa Y. Current
development of lanthanide complexes for bio
medical applications. Chemistry–An Asian
Journal. 2024. 19(7): e202400038. https://doi.
org/10.1002/asia.202400038
9. Lacerda S., Tóth É. Lanthanide complexes in
molecular magnetic resonance imaging and
theranostics. ChemMedChem. 2017. 12(12):
883–894.
https://doi.org/10.1002/cmdc.201700210
10. Bag P., Rastogi C.K., Biswas S., Sivakumar S.,
Mereacre V., Chandrasekhar V. Homodinuc
lear lanthanide {Ln2} (Ln = Gd, Tb, Dy, Eu)
complexes prepared from an o-vanillin based
18 ISSN 2708-129X. Укр. хім. журн., 2025
STRUCTURE AND SPECTRAL EVALUATION OF COVALENCY IN ND(III) TETRAKIS COMPLEXES
WITH CARBACYLAMIDOPHOSPHATE LIGANDS.INORGANIC CHEMISTRY
ligand: Luminescence and single-molecule
magnetism behavior. Dalton Transactions.
2015. 44(9): 4328–4340.
https://doi.org/10.1039/c4dt03429e
11. Gil Y., Aravena D. Understanding Single-
Molecule Magnet properties of lanthanide
complexes from 4f orbital splitting. Dalton
Transactions. 2024. 53(5): 2207–2217.
https://doi.org/10.1039/D3DT04179D
12. Wang J., Sun C.Y., Zheng Q., Wang D.Q., Chen
Y.T., Ju J.F., Tang Y.F. Lanthanide Single‐mo
lecule Magnets: Synthetic strategy, structures,
properties and recent advances. Chemistry–An
Asian Journal. 2023. 18(7): e202201297.
https://doi.org/10.1002/asia.202201297
13. Long J., Guari Y., Ferreira R.A., Carlos L.D.,
Larionova J. Recent advances in luminescent
lanthanide based Single-Molecule Magnets.
Coordination Chemistry Reviews. 2018. 363:
57–70.
https://doi.org/10.1016/j.ccr.2018.02.019
14. Hirai Y. Triboluminescence of lanthanide co-
ordination polymers. Assembled lanthanide
complexes with advanced photophysical pro
perties. Singapore: Springer Singapore. 2018.
81–100.
15. Bünzli J.C.G., Wong K.L. Lanthanide mecha-
noluminescence. Journal of Rare Earths. 2018.
36(1): 1–41.
https://doi.org/10.1016/j.jre.2017.09.005
16. Fontenot R.S., Hollerman W.A., Bhat K.N., Ag-
garwal M.D., Penn B.G. Incorporating strong-
ly triboluminescent europium dibenzoylme
thide triethylammonium into simple polymers.
Polymer journal. 2014. 46(2): 111–116.
https://doi.org/10.1038/pj.2013.78
17. Olawale D.O., Dickens T., Sullivan W.G., Oko-
li O.I., Sobanjo J.O., Wang B. Progress in tri-
boluminescence-based smart optical sensor
system. Journal of Luminescence. 2011. 131(7):
1407–1418. https://doi.org/10.1016/j.jlu-
min.2011.03.015
18. Moynihan S., Van Deun R., Binnemans K.,
Redmond G. Optical properties of planar
polymer waveguides doped with organo-lan-
thanide complexes. Optical Materials. 2007.
29(12): 1821–1830.
https://doi.org/10.1016/j.optmat.2006.10.005
19. Yang J., Diemeer M.B., Geskus D., Sengo G.,
Pollnau M., Driessen A. Neodymium-com-
plex-doped photodefined polymer channel
waveguide amplifiers. Optics letters. 2009.
34(4): 473–475.
https://doi.org/10.1364/ol.34.000473
20. Moynihan S., Van Deun R., Binnemans K.,
Krueger J., von Papen G., Kewell A., Red-
mond G. Organo-lanthanide complexes as
luminescent dopants in polymer waveguides
fabricated by hot embossing. Optical Materi-
als. 2007. 29(12): 1798–1808.
https://doi.org/10.1016/j.optmat.2006.10.010
21. Gao M., Li J., Xia D., Jiang L., Peng N., Zhao
S., Li G. Lanthanides-based security inks with
reversible luminescent switching and self-hea
ling properties for advanced anti-counterfei
ting. Journal of Molecular Liquids. 2022. 350:
118559.
https://doi.org/10.1016/j.molliq.2022.118559
22. Li J., Xia D., Gao M., Jiang L., Zhao S., Li G. In-
visible luminescent inks and luminescent films
based on lanthanides for anti-counterfeiting.
Inorganica Chimica Acta. 2021. 526: 120541.
https://doi.org/10.1016/j.ica.2021.120541
23. Andres J., Hersch R.D., Moser J.E., Chauvin
A.S. A new anti‐counterfeiting feature rely-
ing on invisible luminescent full color images
printed with lanthanide‐based inks. Advanced
Functional Materials. 2014. 24(32): 5029–
5036.
https://doi.org/10.1002/adfm.201400298
24. Carlotto A., Babetto L., Carlotto S., Miozzi M.,
Seraglia R., Casarin M., Armelao L. Lumines-
cent thermometers: from a library of europium
(III) β‐diketonates to a general model for pre-
dicting the thermometric behaviour of europi-
um‐based coordination systems. ChemPhoto-
Chem. 2020. 4(9): 674–684.
https://doi.org/10.1002/cptc.202000116
19https://ucj.org.ua
Mariia B. Struhatska, Nataliia S. Kariaka, Viktor O. Trush, Viktoriya V. Dyakonenko, Svitlana V. Shishkina,
Sergii S. Smola, Nataliia V. Rusakova, Volodymyr M. Amirkhanov UCJ № 11 / Vol. 91
25. Zhernakov M.A., Sedykh A.E., Denisenko
Y.G., Molokeev M.S., Mirzayanov I.I., Becker J.,
Müller-Buschbaum K. Luminescent ther-
mometer systems Dy3+/Eu3+ and Tb3+/
Sm3+ based on coordination compounds: new
pairs to the approved Tb3+/Eu3+?. Chemistry
of Materials. 2024. 36(19): 9704–9717.
https://doi.org/10.1021/acs.chemmater.4c01851
26. Miyata K., Konno Y., Nakanishi T., Kobaya
shi A., Kato M., Fushimi K., Hasegawa Y.
Chameleon luminophore for sensing tempe
ratures: control of metal-to-metal and energy
back transfer in lanthanide coordination po
lymers. Angewandte Chemie. 2013. 125(25).
https://doi.org/10.1002/anie.201301448
27. Wang X.D., Wolfbeis O.S., Meier R.J. Lumi-
nescent probes and sensors for temperature.
Chemical Society Reviews. 2013. 42(19): 7834–
7869.
https://doi.org/10.1039/c3cs60102a
28. Katsagounos G., Stathatos E., Arabatzis N.B.,
Keramidas A.D., Lianos P. Enhanced photon
harvesting in silicon multicrystalline solar
cells by new lanthanide complexes as light
concentrators. Journal of luminescence. 2011.
131(8): 1776–1781.
https://doi.org/10.1016/j.jlumin.2011.04.023
29. Shahi P.K., Singh P., Rai S.B. Sunlight activated
lanthanide complex for luminescent solar col-
lector applications: effect of waveguide matrix.
Journal of Physics D: Applied Physics. 2017.
50(7): 075501.
https://doi.org/10.1088/1361-6463/aa4ecd
30. Bennett S.D., Core B.A., Blake M.P., Pope S.J.,
Mountford P., Ward B.D. Chiral lanthanide
complexes: coordination chemistry, spectro
scopy, and catalysis. Dalton Transactions 2014.
43(15): 5871–5885.
https://doi.org/10.1039/C4DT00114A
31. Dicken R.D., Motta A., Marks T.J. Homolep-
tic lanthanide amide catalysts for organic syn-
thesis: experiment and theory. Acs Catalysis.
2021. 11(5): 2715–2734.
https://doi.org/10.1021/acscatal.0c04882
32. Costa I.F., Blois L., Paolini T.B., Assunção I.P.,
Teotonio E.E., Felinto M.C.F., Brito H.F. Lu-
minescence properties of lanthanide tetrakis
complexes as molecular light emitters. Coordi-
nation Chemistry Reviews. 2024. 502: 215590.
https://doi.org/10.1016/j.ccr.2023.215590
33. Sastri V.R., Perumareddi J.R., Rao V.R., Rayu
du G.V.S., Bünzli J.C. Modern aspects of rare
earths and their complexes. Amsterdam: Else-
vier. 2003. ISBN 0444510109
34. Amirkhanov V., Ovchynnikov V., Trush V.,
Gawryszewska P., Jerzykiewicz L.B. Power-
ful new ligand systems: carbacylamidophos-
phates (CAPh) and sulfonylamidophosphates
(SAPh). Ligands: Synthesis, Characterization
and Role in Biotechnology. New York: NOVA
publishers. 2014. 199–248.
35. Kariaka N.S., Lipa A., Carneiro Neto A.N.,
Malta O.L., Gawryszewska P. and Amirkhanov
V.M. Eu3+ and Tb3+ coordination com-
pounds with phenyl-containing carbacylami-
dophosphates: comparison with selected Ln3+
β-diketonates. Frontiers in Chemistry. 2023.
11: 1188314.
https://doi.org/10.3389/fchem.2023.1188314
36. Sinha S.P. Spectroscopic investigations of
some neodymium complexes. Spectrochimica
Acta. 1966. 22(1): 57–62.
https://doi.org/10.1016/0371-1951(66)80008-5
37. Carnall W.T., Fields P.R., Rajnak K. Electro
nic energy levels in the trivalent lanthanide
aquo ions. I. Pr3+, Nd3+, Pm3+, Sm3+, Dy3+,
Ho3+, Er3+, and Tm3+. The Journal of chemi-
cal physics. 1968. 49(10): 4424–4442.
https://doi.org/10.1063/1.1669893
38. Wybourne B.G., Meggers W.F. Spectrosco
pic properties of rare earths. New York: John
Wiley. 1965. 236.
39. Agarwal R.K., Prasad S., Garg R., Sidhu S.K.
Synthesis and preliminary structural charac-
terization of some lanthanide (III) semicarba-
zone complexes. Bulletin of the Chemical So
ciety of Ethiopia. 2006. 20(1): 167–172.
http://dx.doi.org/10.4314/bcse.v20i1.21157
20 ISSN 2708-129X. Укр. хім. журн., 2025
STRUCTURE AND SPECTRAL EVALUATION OF COVALENCY IN ND(III) TETRAKIS COMPLEXES
WITH CARBACYLAMIDOPHOSPHATE LIGANDS.INORGANIC CHEMISTRY
40. Sinha S.P. Ternary Lanthanide Complexes of
the Type [M(HMPA)4(NO3)3]: A new me
thod of synthesis and spectroscopic studies in-
cluding a comparison of the electronic spect
ra of the [M(HMPA)x(ClO4)3] complexes.
Zeitschrift für anorganische und allgemeine
Chemie. 1977. 434(1): 277–292.
https://doi.org/10.1002/zaac.19774340134
41. Wyart J.F., Meftah A., Bachelier A., Sinzelle J.,
Tchang-Brillet W.Ü.L., Champion N., Sugar J.
Energy levels of 4f3 in the Nd3+ free ion from
emission spectra. Journal of Physics B: Atomic,
Molecular and Optical Physics. 2006. 39(5):
L77.
http://dx.doi.org/10.1088/0953-4075/39/5/L01
42. Gao F., Zhang S. Investigation of mechanism
of nephelauxetic effect. Journal of Physics and
Chemistry of Solids. 1997. 58(12): 1991–1994.
https://doi.org/10.1016/S0022-3697(96)00139-4
43. Ryan J.L., Jørgensen C.K. Absorption spectra
of octahedral lanthanide hexahalides. The Jour-
nal of Physical Chemistry. 1966. 70(9): 2845–
2857. https://doi.org/10.1021/j100881a021
44. Davidenko N.K., Yatsimirskii K.B. Determina-
tion of metal-ligand distances from the posi-
tion of the spectral bands in lanthanide com-
plexes. Dokl. Akad. Nauk SSSR. 1970. 191(2):
384-387. (in Russian).
45. Karraker D.G. Hypersensitive transitions of
six-, seven-, and eight-coordinate neodymi-
um, holmium, and erbium chelates. Inorganic
chemistry. 1967. 6(10): 1863–1868.
http://dx.doi.org/10.1021/ic50061a018
46. Karraker D.G. Spectral studies on the Nd3+
and Er3+ chelates of heptafluorodimethyloc-
tanedione. Journal of Inorganic and Nuclear
Chemistry. 1971. 33(11): 3713–3718.
https://doi.org/10.1016/0022-1902(71)80278-6
47. Kariaka N.S., Kolotilov S.V., Gawryszewska
P., Kasprzycka E., Weselski M., Dyakonenko
V.V., Shishkina S.V., Trush V.A., Amirkhanov
V.M. Structures and spectral and magnetic
properties of a series of carbacylamidophos-
phate pentanuclear lanthanide(III) hydroxo
complexes. Inorganic Chemistry. 2019. 58 (21):
14682–14692.
https://doi.org/10.1021/acs.inorgchem.9b0
2354
48. Pham Y.H., Trush V.A., Korabik M., Amir
khanov V.M., Gawryszewska P. Nd3+ and
Yb3+ complexes with N-(diphenylphospho-
ryl) pyrazine-2-carboxamide as UV-NIR ra
diation converters and single-ion magnets.
Dyes and Pigments. 2021. 186: 108986.
http://dx.doi.org/10.1016/j.dyepig.2020.108986
49. Lyle S.J., Rahman M.M. Complexometric ti-
tration of yttrium and the lanthanons—I:
A comparison of direct methods. Talanta.
1963. 10(11): 1177–1182.
https://doi.org/10.1016/0039-9140%2863%
2980170-8
50. Dolomanov O.V., Bourhis L.J., Gildea R.J.,
Howard J.A., Puschmann H. OLEX2: a comp
lete structure solution, refinement and ana
lysis program. Applied Crystallography. 2009.
42(2): 339–341.
https://doi.org/10.1107/S0021889808042726
51. Sheldrick G.M. SHELXT – Integrated space-
group and crystal-structure determination.
Foundations of Crystallography. 2015. 71(1):
3–8.
https://doi.org/10.1107/S2053273314026370
52. Sheldrick G.M. Crystal structure refinement
with SHELXL. Crystal Structure Communica-
tions. 2015. 71(1): 3–8.
https://doi.org/10.1107/S2053229614024218
53. Savchuk M.O., Litsis O.O., Sliva T.Yu., Trush
V.A., Amirkhanov V.M. Synthesis of diphe-
nyl-N-trichloroacetylamidophosphate and IR
spectroscopic investigations of REE anionic
coordination compounds on its base. Voprosy
khimii i khimicheskoi tekhnologii. 2017. 6: 44–
49. ISSN 0321-4095
54. Savchuk M.O., Litsis O.O., Kariaka N.S.,
Trush V.O., Dyakonenko V.V., Smola S.S.,
Amirkhanov V.M. Polymeric sodium salts and
monomeric lanthanide coordination com-
pounds with diphenyl-N-trichloroacetylami-
21https://ucj.org.ua
Mariia B. Struhatska, Nataliia S. Kariaka, Viktor O. Trush, Viktoriya V. Dyakonenko, Svitlana V. Shishkina,
Sergii S. Smola, Nataliia V. Rusakova, Volodymyr M. Amirkhanov UCJ № 11 / Vol. 91
dophosphate: synthesis and characterization.
Inorganica Chimica Acta. 2024. 559: 121783.
https://doi.org/10.1016/j.ica.2023.121783
55. Llunell M., Casanova D., Cirera J., Alemany P.,
Alvarez S. SHAPE, Ver. 2.0. University of Bar-
celona: Barcelona, Spain. 2010.
56. Amirkhanov V.M., Trush V.A. Properties
and structure of dimethyl ether of trichloro-
acetylamidophosphoric acid. Russian Journal
of General Chemistry. 1995. 65(7): 1120–1124.
(in Russian).
57. Kariaka N.S., Dyakonenko V.V., Znovjyak
K.O., Shishkina S.V., Amirkhanov V.M.
Synthesis, crystal structure and Hirshfeld
surface analysis of the tetrakis complex
NaNdPyr4(i-PrOH)2·i-PrOH with a carbacy-
lamidophosphate of the amide type. Structure
Reports. 2023. 79(12): 1218–1222.
https://doi.org/10.1107/S2056989023010071
58. Litsis O.O., Ovchynnikov V.A., Scherbatskii
V.P., Nedilko S.G., Sliva T.Y., Dyakonenko V.V.,
Amirkhanov V.M. Lanthanide mixed-ligand
complexes of the [Ln(CAPh)3(Phen)] and
[LaxEu1-x(CAPh)3(Phen)] (CAPh= carbacyl
amidophosphate) type. A comparative study
of their spectral properties. Dalton Transacti
ons. 2015. 44(35): 15508–15522.
https://doi.org/10.1039/C5DT02557E
59. Sokolnicki J., Legendziewicz J., Amirkhanov W.,
Ovchinnikov V., Macalik L., Hanuza J. Com-
parative optical studies of lanthanide complex-
es with three types of phosphoro-azo deriva-
tives of β-diketones. Spectrochimica Acta Part
A: Molecular and Biomolecular Spectroscopy.
1999. 55(2): 349–367.
https://doi.org/10.1016/S1386-1425(98)00193-0
60. Coates J. Interpretation of infrared spectra, a
practical approach. Encyclopedia of analytical
chemistry. 2000. 12: 10815–10837.
https://doi.org/10.1002/9780470027318.a5606
61. Silverstein R.M., Webster F.X., Kiemle D.J.,
Bryce D.L. Spectrometric identification of or-
ganic compounds. – 8th ed. Wiley. 2014. 464.
62. Yatsimirskii K.B., Davidenko N.K. Absorption
spectra and structure of lanthanide coordi-
nation compounds in solution. Coordination
Chemistry Reviews. 1979. 27(3): 223–273.
https://doi.org/10.1016/S0010-8545(00)820
68-8
63. Kariaka N.S., Trush V.A., Medviediev V.V.,
Dyakonenko V.V., Shishkin O.V., Smola S.S.,
Amirkhanov V.M. Coordination compounds
based on CAPh type ligand: synthesis, struc-
tural characteristics and luminescence pro
perties of tetrakis-complexes CsLnL4 with
dimethylbenzoylamidophosphate. Journal of
Coordination Chemistry. 2016. 69(1): 123–134.
http://dx.doi.org/10.1080/00958972.2015.111
5024
64. Znovjyak K.O., Moroz O.V., Ovchynnikov
V.A., Sliva T.Y., Shishkina S.V., Amirkhanov
V.M. Synthesis and investigations of mixed-li-
gand lanthanide complexes with N,N′-dipy-
rrolidine-N′′-trichloracetylphosphortriamide,
dimethyl-N-trichloracetylamidophosphate,
1,10-phenanthroline and 2,2′-bipyrimidine.
Polyhedron. 2009. 28(17): 3731–3738.
https://doi.org/10.1016/J.POLY.2009.08.017
65. Henrie D.E., Choppin G.R. Environmental ef-
fects on f–f transitions. II. “Hypersensitivity”
in some complexes of trivalent neodymium.
The Journal of Chemical Physics. 1968. 49(2):
477–481.
https://doi.org/10.1063/1.1670099
66. Kariaka N.S., Trush V.A., Dyakonenko V.V.,
Shishkina S.V., Smola S.S., Rusakova N.V.,
Sliva T.Y., Gawryszewska P., Carneiro Neto
A.N., Malta O.L., Amirkhanov V.M. New
luminescent lanthanide tetrakis‐complexes
NEt4[LnL4] based on dimethyl‐N‐benzoyl-
amidophosphate. ChemPhysChem. 2022.
23(14): e202200129.
https://doi.org/10.1002/cphc.202200129
Cтаття надійшла 17.09.2025.
|
| id | oai:ojs2.1444248.nisspano.web.hosting-test.net:article-755 |
| institution | Ukrainian Chemistry Journal |
| keywords_txt_mv | keywords |
| language | English |
| last_indexed | 2026-07-23T01:13:52Z |
| publishDate | 2025 |
| publisher | V.I.Vernadsky Institute of General and Inorganic Chemistry |
| record_format | ojs |
| resource_txt_mv | ucjorgua/07/c0db77ba8db5e628e3ceba880450e207.pdf |
| spelling | oai:ojs2.1444248.nisspano.web.hosting-test.net:article-7552026-07-22T08:23:56Z STRUCTURE AND SPECTRAL EVALUATION OF COVALENCY IN ND(III) TETRAKIS COMPLEXES WITH CARBACYLAMIDOPHOSPHATE LIGANDS Struhatska, Mariia Kariaka, Nataliia Trush, Viktor Dyakonenko, Viktoriya Shishkina, Svitlana Smola, Sergii Rusakova, Nataliia Amirkhanov, Volodymyr NdIII, carbacylamidophosphate, tetrakis complex, tetraethylammonium cation, electronic spectroscopy, crystal structure. Two neodymium(III) tetrakis complexes with different carbacylamidophosphate ligands and a tetraethylammonium cation of the formulas NEt4[NdL14] (1Nd) and NEt4[NdL24]·iPrOH (2Nd) were synthesized, where [L1]⁻ is dimethyl-N-trichloroacetylamidophosphate, Cl3CC(O)NP(O)(OCH3)2⁻, and [L2]⁻ is diphenyl-N-trichloroacetylamidophosphate, Cl3CC(O)NP(O)(OC6H5)2⁻. The compounds were characterized by elemental analysis, infrared spectroscopy, diffuse reflectance electronic spectroscopy, and single-crystal X-ray diffraction analysis. Structural analysis confirmed the formation of anionic complexes featuring a NdO8 coordination environment. Coordination polyhedra of central ions are best described as a triangular dodecahedron for 1Nd and a square antiprism for 2Nd. Diffuse reflectance spectra in the UV–vis–NIR region revealed characteristic f–f transitions of NdIII, with ligand-dependent modulation of band shape and intensity of the “hypersensitive” transitions. The bonding between the metal and the ligands was found to have weak covalent character. Luminescence studies of the 2Nd complex revealed weak emission sensitization by the ligands. V.I.Vernadsky Institute of General and Inorganic Chemistry 2025-12-25 Article Article Inorganic Chemistry Неорганическая химия Неорганічна хімія application/pdf https://ucj.org.ua/index.php/journal/article/view/755 10.33609/2708-129X.91.11.2025.3-21 Ukrainian Chemistry Journal; Vol. 91 No. 11 (2025): Ukrainian Chemistry Journal; 3-21 Украинский химический журнал; ##issue.vol## 91 ##issue.no## 11 (2025): Ukrainian Chemistry Journal; 3-21 Український хімічний журнал; Том 91 № 11 (2025): Ukrainian Chemistry Journal; 3-21 2708-129X 2708-1281 en https://ucj.org.ua/index.php/journal/article/view/755/390 Copyright (c) 2025 Mariia Struhatska, Nataliia Kariaka, Viktor Trush, Viktoriya Dyakonenko, Svitlana Shishkina, Sergii Smola, Nataliia Rusakova, Volodymyr Amirkhanov https://creativecommons.org/licenses/by-nc/4.0 |
| spellingShingle | Struhatska, Mariia Kariaka, Nataliia Trush, Viktor Dyakonenko, Viktoriya Shishkina, Svitlana Smola, Sergii Rusakova, Nataliia Amirkhanov, Volodymyr STRUCTURE AND SPECTRAL EVALUATION OF COVALENCY IN ND(III) TETRAKIS COMPLEXES WITH CARBACYLAMIDOPHOSPHATE LIGANDS |
| title | STRUCTURE AND SPECTRAL EVALUATION OF COVALENCY IN ND(III) TETRAKIS COMPLEXES WITH CARBACYLAMIDOPHOSPHATE LIGANDS |
| title_full | STRUCTURE AND SPECTRAL EVALUATION OF COVALENCY IN ND(III) TETRAKIS COMPLEXES WITH CARBACYLAMIDOPHOSPHATE LIGANDS |
| title_fullStr | STRUCTURE AND SPECTRAL EVALUATION OF COVALENCY IN ND(III) TETRAKIS COMPLEXES WITH CARBACYLAMIDOPHOSPHATE LIGANDS |
| title_full_unstemmed | STRUCTURE AND SPECTRAL EVALUATION OF COVALENCY IN ND(III) TETRAKIS COMPLEXES WITH CARBACYLAMIDOPHOSPHATE LIGANDS |
| title_short | STRUCTURE AND SPECTRAL EVALUATION OF COVALENCY IN ND(III) TETRAKIS COMPLEXES WITH CARBACYLAMIDOPHOSPHATE LIGANDS |
| title_sort | structure and spectral evaluation of covalency in nd(iii) tetrakis complexes with carbacylamidophosphate ligands |
| topic_facet | NdIII carbacylamidophosphate tetrakis complex tetraethylammonium cation electronic spectroscopy crystal structure. |
| url | https://ucj.org.ua/index.php/journal/article/view/755 |
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