Phase diagrams of the quasi-binary systems Cu2S–SiS2 and Cu2SiS3–PbS and the crystal structure of the new quaternary compound Cu2PbSiS4

Isothermal section of the Ag2S–PbS–GeS2 system at 300K and the crystal structure of Ag2PbGeS4

“…The coordination surrounding of Pb, the heaviest atom, is characterized by eight sulfur atoms forming a two-capped trigonal prism. Such surrounding of the Pb atoms is observed also in a quaternary compound Cu 2 PbSiS 4 [3]. The Pb-S distances ranging from 0.2950(5)-0.33465(5) nm in Ag 2 PbGeS 4 are similar to those in Cu 2 PbSiS 4 (0.3011-0.3222 nm) [3] and PbGa 2 S 4 compounds (0.2790-0.3276 nm) [19].…”

“…Such surrounding of the Pb atoms is observed also in a quaternary compound Cu 2 PbSiS 4 [3]. The Pb-S distances ranging from 0.2950(5)-0.33465(5) nm in Ag 2 PbGeS 4 are similar to those in Cu 2 PbSiS 4 (0.3011-0.3222 nm) [3] and PbGa 2 S 4 compounds (0.2790-0.3276 nm) [19]. Smaller-sized cations Ag and Ge are surrounded by the tetrahedra of sulfur atoms.…”

“…However, as the most typical oxidation state of lead is +2, it was suggested to test its position as a B II element. In the copper-containing systems, only one compound, Cu 2 PbSiS 4 , was discovered that crystallizes in the trigonal structure (S.G. P3 2 21, a = 0.60565 nm, c = 1.51841 nm) [3].…”

Phase equilibria in the Tl2S–PbS–GeS2 system and crystal structure of Tl0.5Pb1.75GeS4

“…Their sets of properties make them of interest for infrared and non-linear optics and semiconductor technology. Two compounds were also found for B II = Pb; Cu 2 PbSiS 4 crystallizes in the trigonal S.G. P3 2 21 with the lattice parameters a = 0.60565, c = 1.51841 nm [2], and Ag 2 PbGeS 4 has an orthorhombic structure (S.G. Ama2 with the lattice parameters a = 1.02390, b = 1.02587, c = 0.67701 nm) [3]. The Ag 2 S-PbS-GeS 2 system also features the existence of Ag 0.5 Pb 1.75 GeS 4 , which crystallizes in the non-centrosymmetric cubic S.G. I-43d, a = 1.40277 nm [4].…”

Fabrication and characterization of ternary Cu8SiS6 and Cu8SiSe6 thin film layers for optoelectronic applications

“…In the present contribution we have fabricated and characterized thin film Cu8SiS6 and Cu8SiSe6 layers, in order to find out if they can be suitable as high band gap thin film solar cell absorber layers. Up to date, little was known on these two chalcogenide materials, as only structural characterization has been performed so far with some very basic electrical characterization on grain-like samples [5][6][7][8] .…”