Crystal structure and magnetic properties of titanium-based CuTi2−xMxS4 and CuCr2−xTixSe4 chalcospinels

Crystal structure, Raman scattering and magnetic properties of CuCr2−Zr Se4 and CuCr2−Sn Se4 selenospinels

“…The SeM 3 Cu tetrahedron is the most distorted polyhedron ( 8 % distortion from an ideal tetrahedron). These values compare very well with those found for CuCr 2-x Ti x Se 4[11] .…”

“…The Cu-Se distances in CuCr 2-x Zr x Se 4 are 2.368(9) Å (x = 0.2) and 2.3839(8) Å (x = 0.5). The Cu-Se distances compare well with those found in cubic CuCr 2-x Ti x Se 4 (2.3701 to 2.3716 Å)[11]. In both CuCr 1.8 Zr 0.2 Se 4 and CuCr 1.5 Zr 0.5 Se 4 compounds, the bond distances of (Cr/Zr)-Se (2.538(12)to 2.5557(5) Å, respectively) are consistent with the bond length in cubic CuCrZrSe 4 (2.614 Å) [25].…”

“…Several studies on CuCr 2-x M x Q 4 spinels revealed that whereas copper exists as the diamagnetic Cu + cation the M atoms array exist in the 4+ oxidation state (M = Ti, Zr, Hf), thus changing the properties of the original material [11][12][13][14][15]. Thus, the chemical substitutions of chromium in CuCr 2 Se 4 end-member by M 4+ cations play an important role in the particular magnetic/electrical properties of these compounds.…”

Crystal Structure Classification of Copper‐Based Sulfides as a Tool for the Design of Inorganic Functional Materials

“…Chemie 966.0 3 ), [66] which contains CuS 4 tetrahedra and (Ti,Co)S 6 octahedra, and the synthetic phase Cu 4 Sn 7 S 16 (R3 ¯m, a = 7.372 , c = 36.010 , V = 1694.8 3 ), [67] which contains CuS 6 and SnS 6 octahedra as well as CuS 4 tetrahedra, some of them leaning strongly toward aC uS 3 trigonal-planar coordination (Figure 6c). Essentially,t he crystal structure of Cu 4 Sn 7 S 16 can be described as ad efect (thio)spinel AB 2 X 4 (unit cell parameter a' % 10.…”

Crystal Structure Classification of Copper‐Based Sulfides as a Tool for the Design of Inorganic Functional Materials

“…Note that Cu 4 SnS 4 ,t etrahedrite,a nd talnakhite,d espite the aforementioned differences,e xhibit extremely low thermal conductivity. [59,61,62,64,65] Group Ealso includes n-type compounds (Cu/M < 1) such as thiospinel Cu 2 CoTi 3 S 8 (Fd3 ¯m, a = 9.885 , V = 966.0 3 ), [66] which contains CuS 4 tetrahedra and (Ti,Co)S 6 octahedra, and the synthetic phase Cu 4 Sn 7 S 16 (R3 ¯m, a = 7.372 , c = 36.010 , V = 1694.8 3 ), [67] which contains CuS 6 and SnS 6 octahedra as well as CuS 4 tetrahedra, some of them leaning strongly toward aC uS 3 trigonal-planar coordination (Figure 6c). Essentially,t he crystal structure of Cu 4 Sn 7 S 16 can be described as ad efect (thio)spinel AB 2 X 4 (unit cell parameter a' % 10.…”