Monoclinic Cu₂Se₃Sn

Abstract

A previously unknown modification of dicopper(I) triselenostannate(IV), Cu(2)Se(3)Sn, has been obtained from the Cu(2)Se-SnSe(2) quasi-binary system and investigated using X-ray single-crystal diffraction. The Se atoms are stacked in a closest-packed arrangement with the layers in the sequence ABC. The Cu atoms occupy one-third of the tetrahedral interstices, whereas the Sn atoms are located in one-sixth of the tetrahedral interstices. All the atoms occupy general positions. The structure possesses pseudo-inversion symmetry. The Cu(2)Se(3)Sn structure investigated in this paper (96 atoms per unit cell, ordered distribution of Cu and Sn over 12 cation positions) is a superstructure of the reported cubic (eight atoms per unit cell, random distribution of Cu and Sn over one cation position) and monoclinic (24 atoms per unit cell, ordered distribution of Cu and Sn over three cation positions) modifications.

Crystal structure of Cu2Se

“…The remaining symmetry-independent copper atoms are located close to the plane of a triangular face (CN = 3). The crystal structure of LT-Cu 2 Se is related to the structure of the recently investigated compound Cu 2 SnSe 3 [10] (Fig. 4).…”

Structural evolvement and thermoelectric properties of Cu3−xSnxSe3 compounds with diamond-like crystal structures

“…1, 2). The sample with x = 1.05 crystallizes in the monoclinic-III 65 structure 24 (Fig. 3, right) along with about 5% of impurity phase SnSe.…”

Thermoelectric properties of S and Te-doped Cu2SnSe3 prepared by combustion synthesis

“…Cu 2 SnSe 3 is a p-type semiconductor with a narrow gap and can crystallize into a cubic or monoclinic phase depending on the synthesis conditions [13][14][15][16][17][18]. In Cu 2 SnSe 3 , the Cu-Se bonds stabilize the structure and form an electrically conductive framework, and Sn atoms reside in the framework and donate electrons to balance the structure [9].…”