Materials Data on LiFeAs by Materials Project

Abstract

LiFeAs is Matlockite structured and crystallizes in the tetragonal P4/nmm space group. The structure is three-dimensional. Li1+ is bonded to five equivalent As3- atoms to form distorted LiAs5 trigonal bipyramids that share corners with twelve equivalent FeAs4 tetrahedra, corners with four equivalent LiAs5 trigonal bipyramids, edges with four equivalent FeAs4 tetrahedra, and edges with eight equivalent LiAs5 trigonal bipyramids. There are one shorter (2.71 Å) and four longer (2.76 Å) Li–As bond lengths. Fe2+ is bonded to four equivalent As3- atoms to form FeAs4 tetrahedra that share corners with four equivalent FeAs4 tetrahedra, corners with twelve equivalent LiAs5 trigonal bipyramids, edges with four equivalent FeAs4 tetrahedra, and edges with four equivalent LiAs5 trigonal bipyramids. All Fe–As bond lengths are 2.34 Å. As3- is bonded in a 9-coordinate geometry to five equivalent Li1+ and four equivalent Fe2+ atoms.