Materials Data on CrAgSnSe4 by Materials Project

CrAgSnSe4 is Spinel-derived structured and crystallizes in the orthorhombic Imma space group. The structure is three-dimensional. Cr3+ is bonded to six Se2- atoms to form CrSe6 octahedra that share corners with six equivalent AgSe4 tetrahedra, edges with two equivalent CrSe6 octahedra, and edges with four equivalent SnSe6 octahedra. There are two shorter (2.55 Å) and four longer (2.59 Å) Cr–Se bond lengths. Ag1+ is bonded to four Se2- atoms to form AgSe4 tetrahedra that share corners with six equivalent CrSe6 octahedra and corners with six equivalent SnSe6 octahedra. The corner-sharing octahedra tilt angles range from 51–66°. There are two shorter (2.63 Å) and two longer (2.64 Å) Ag–Se bond lengths. Sn4+ is bonded to six Se2- atoms to form SnSe6 octahedra that share corners with six equivalent AgSe4 tetrahedra, edges with two equivalent SnSe6 octahedra, and edges with four equivalent CrSe6 octahedra. All Sn–Se bond lengths are 2.75 Å. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a rectangular see-saw-like geometry to one Cr3+, one Ag1+, and two equivalent Sn4+ atoms. In the second Se2- site, Se2- is bonded in a distorted rectangular see-saw-like geometry to two equivalent Cr3+, one Ag1+, and one Sn4+ atom.CrAgSnSe4为尖晶石衍生结构，结晶于正交晶系的Imma空间群。其结构为三维框架结构。Cr³+与6个Se²-原子配位，形成CrSe₆八面体；该八面体与6个等价的AgSe₄四面体共享顶点，与2个等价的CrSe₆八面体共享棱，同时与4个等价的SnSe₆八面体共享棱。Cr-Se键长分为两组：2个较短键长为2.55 Å，4个较长键长为2.59 Å。Ag⁺与4个Se²-原子配位，形成AgSe₄四面体；该四面体与6个等价的CrSe₆八面体以及6个等价的SnSe₆八面体共享顶点。共顶八面体的倾斜角范围为51°至66°。Ag-Se键长分为两组：2个较短键长为2.63 Å，2个较长键长为2.64 Å。Sn⁴+与6个Se²-原子配位，形成SnSe₆八面体；该八面体与6个等价的AgSe₄四面体共享顶点，与2个等价的SnSe₆八面体共享棱，同时与4个等价的CrSe₆八面体共享棱。所有Sn-Se键长均为2.75 Å。体系中存在两种不等价的Se²-位点：在第一种Se²-位点中，Se²-以矩形跷跷板型配位几何与1个Cr³+、1个Ag⁺以及2个等价的Sn⁴+原子成键；在第二种Se²-位点中，Se²-以畸变矩形跷跷板型配位几何与2个等价的Cr³+、1个Ag⁺以及1个Sn⁴+原子成键。