Lithuanian Journal of Physics article / Lietuvos fizikos žurnalo straipsnis

STRUCTURAL AND ELECTRICAL PROPERTIES OF ARGYRODITE-TYPE Cu₇PS₆ CRYSTALS
Ihor P. Studenyak^a, Vitalii Yu. Izai^a, Artem I. Pogodin^a, Oleksandr P. Kokhan^a, Vasil I. Sidey^a, Mar'yan Yu. Sabov^a, Algimantas Kežionis^b, Tomas Šalkus^b, and Jūras Banys^b
^aUzhhorod National University, 46 Pidhirna Str., 88000 Uzhhorod, Ukraine
^bFaculty of Physics, Vilnius University, Saulėtekio 9/3, 10222 Vilnius, Lithuania
tomas.salkus@ff.vu.lt

Received 16 June 2017; revised 14 July 2017; accepted 20 September 2017

Cu₇PS₆ crystals were grown using direct crystallisation from the melt (Bridgman–Stockbarger technique). The crystal structure of Cu₇PS₆ was determined by X-ray powder diffraction. Cu₇PS₆ crystallise in the cubic structure, space group P2₁3 (No. 198), the lattice parameter a = 9.6706(1) Å, formula units per cell Z = 4. Electrical properties of Cu₇PS₆ crystals were studied in the frequency range 10–10¹⁰ Hz and in the temperature interval 296–351 K. The performed analysis shows that the Cu₇PS₆ crystals are mixed electron-ionic conductors with some growth defects.

Keywords: inorganic materials, crystal growth, crystal structure, X-ray diffraction, charge transport
PACS: 81.10.-h, 84.37.+q, 61.05.cp

ARGIRODITO TIPO Cu₇PS₆ KRISTALŲ STRUKTŪRA IR ELEKTRINĖS SAVYBĖS
Ihor P. Studenyak^a, Vitalii Yu. Izai^a, Artem I. Pogodin^a, Oleksandr P. Kokhan^a, Vasil I. Sidey^a, Mar'yan Yu. Sabov^a, Algimantas Kežionis^b, Tomas Šalkus^b, Jūras Banys^b

^aUžhorodo nacionalinis universitetas, Užhorodas, Ukraina
^bVilniaus universiteto Fizikos fakultetas, Vilnius, Lietuva

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