Електронна структура та можливість експериментального моніторингу фазового складу кристалів полівініліденфториду (PVDF)

• Дата: 2025
• Автори: Baranchykov, Z., Hizhnyi, Yu., Makarenko, O., Nedilko, S.G.
• Формат: Стаття
• Мова: English; Ukrainian
• Опубліковано: Publishing house "Academperiodika" 2025
• Теми: полiвiнiлiденфторид; кристал; електронна структура; оптичнi спектри; фазовий склад
• Онлайн доступ: https://ujp.bitp.kiev.ua/index.php/ujp/article/view/2023483
• Назва журналу: Ukrainian Journal of Physics

The organic polymer polyvinylidene fluoride (PVDF) is a promising and commercially attractive material for the modern needs of nanotechnology and microelectronics and biomedicine. Detecting the phase composition of PVDF blends is an important technological task. This paper presents the results of ab initio calculations of the electronic band structure of the three most common phases of polyvinylidene fluoride crystals α-, β- and γ-PVDF. The band dispersion curves, partial densities of electronic states, spatial distributions of electronic densities, spectra of dielectric constants, complex refractive index, absorption and reflection, infrared absorption spectra, Raman scattering and X-ray diffraction patterns of α-, β- and γ-phases of PVDF were obtained and analyzed. Analysis of the results of electronic structure calculations allowed to draw a number of conclusions regarding the peculiarities of formation of electronic and optical properties of the α-, β-, and γ-phases of PVDF crystal, as well as to make some predictions about the possibility of experimental monitoring of the phase composition of this compound. It has been established that detection of the simultaneous presence of β- and α- (or γ-) phases in PVDF crystal samples can be effectively performed by vacuum ultraviolet reflection spectroscopy, infrared absorption, Raman spectroscopy, and X-ray diffraction analysis. The presence of the α- phase on the background of the γ-phase of PVDF will be practically impossible to detect using these methods.