Materials Data on LaF3 by Materials Project

Abstract

LaF3 is alpha bismuth trifluoride structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. La3+ is bonded to twelve F1- atoms to form LaF12 cuboctahedra that share corners with four equivalent LaF12 cuboctahedra, corners with eight equivalent FLa4F8 cuboctahedra, corners with sixteen equivalent FLa4F4 tetrahedra, edges with eight equivalent LaF12 cuboctahedra, edges with eight equivalent FLa4F4 tetrahedra, faces with four equivalent LaF12 cuboctahedra, and faces with six equivalent FLa4F8 cuboctahedra. There are eight shorter (2.56 Å) and four longer (2.75 Å) La–F bond lengths. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded to four equivalent La3+ and four equivalent F1- atoms to form distorted FLa4F4 tetrahedra that share corners with eight equivalent LaF12 cuboctahedra, corners with eight equivalent FLa4F8 cuboctahedra, corners with eight equivalent FLa4F4 tetrahedra, edges with four equivalent LaF12 cuboctahedra, edges with four equivalent FLa4F8 cuboctahedra, edges with twelve equivalent FLa4F4 tetrahedra, and faces with six equivalent FLa4F4 tetrahedra. All F–F bond lengths are 2.56 Å. In the second F1- site, F1- is bonded to four equivalent La3+ and eight equivalent F1- atoms to form distorted FLa4F8 cuboctahedra that share corners with four equivalent FLa4F8 cuboctahedra, corners with eight equivalent LaF12 cuboctahedra, corners with sixteen equivalent FLa4F4 tetrahedra, edges with eight equivalent FLa4F8 cuboctahedra, edges with eight equivalent FLa4F4 tetrahedra, faces with four equivalent FLa4F8 cuboctahedra, and faces with six equivalent LaF12 cuboctahedra.