Structure and Raman spectra of (Cu6PS5I)1–x(Cu7PS6)x mixed crystals - I. P. Studenyak; M. M. Luchynets; Yu. Izai; A. I. Pogodin; O. P. Kokhan; Yu. M. Azhniuk; D. R.T. Zahn (Semiconductor Physics, Quantum Electronics and Optoelectronics, 2017)