Structural and optical properties of (Cu6PS5Br)1-x(Cu7PS6)x mixed crystals

• Published in: Journal of alloys and compounds Vol. 782; pp. 586 - 591
• Main Authors: Studenyak, I.P., Luchynets, M.M., Izai, V. Yu, Pogodin, A.I., Kokhan, O.P., Azhniuk, Yu.M., Zahn, D.R.T.
• Format: Journal Article
• Language: English
• Published: Lausanne Elsevier B.V 25.04.2019; Elsevier BV
• Subjects: Bridgman method; Crystal growth; Crystal lattices; Crystal structure; Crystals; Dependence; Diffuse reflection; Energy gap; Face centered cubic lattice; Inorganic materials; Mixed crystals; Optical properties; Raman scattering; Raman spectra; X-ray diffraction; Crystal growth; X-ray diffraction; Raman scattering; Diffuse reflection; Inorganic materials; Crystal structure
• ISSN: 0925-8388; 1873-4669
• DOI: 10.1016/j.jallcom.2018.12.214

The structure and optical properties of Bridgman-grown (Cu6PS5Br)1-x(Cu7PS6)x mixed crystals are reported. X-ray diffraction data reveal a face-centred cubic lattice (F4¯3m space group) for Cu6PS5Br-rich crystals (0 < x < 0.4) and a primitive cubic lattice (P213 space group) for Cu7PS6-rich (0.4 < x < 1) crystals. These structural data correlate with the Raman spectra where, besides the common features typical for the argyrodite-type Cu6PS5Br and Cu7PS6 crystals, weaker bands characteristic only for the end-point compounds are observed in the corresponding compositional intervals. Based on the spectral position of the short-wavelength edge of diffuse reflection spectra, the compositional dependence of the energy gap is studied exhibiting a nonlinear behaviour. [Display omitted] •Structure and optical properties of (Cu6PS5Br)1-x(Cu7PS6)x crystals are reported.•Structural data of (Cu6PS5Br)1-x(Cu7PS6)x crystals correlate with Raman spectra.•Compositional dependence of the energy gap shows the nonlinear behaviour.