Materials Data on Sr(GaSe2)2 by Materials Project
SrGa2Se4 crystallizes in the orthorhombic Cccm space group. The structure is three-dimensional. Sr2+ is bonded in a 8-coordinate geometry to eight Se2- atoms. There are four shorter (3.29 Å) and four longer (3.32 Å) Sr–Se bond lengths. Ga3+ is bonded to four Se2- atoms to form edge-sharing GaSe4 tetrahedra. There are a spread of Ga–Se bond distances ranging from 2.43–2.47 Å. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 4-coordinate geometry to two equivalent Sr2+ and two equivalent Ga3+ atoms. In the second Se2- site, Se2- is bonded to two equivalent Sr2+ and two equivalent Ga3+ atoms to form a mixture of distorted edge and corner-sharing SeSr2Ga2 trigonal pyramids.