LiMnSe2 crystallizes in the trigonal P3m1 space group. Li(1) is bonded in a 3-coordinate geometry to three equivalent Se(1) and three equivalent Se(2) atoms. Mn(1) is bonded to one Se(1) and three equivalent Se(2) atoms to form corner-sharing MnSe4 tetrahedra. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to three equivalent Li(1) and one Mn(1) atom to form corner-sharing SeLi3Mn tetrahedra. In the second Se site, Se(2) is bonded in a distorted trigonal non-coplanar geometry to three equivalent Li(1) and three equivalent Mn(1) atoms.
LiMnSe2 crystallizes in the trigonal P3m1 space group. Li(1) is bonded in a 3-coordinate geometry to three equivalent Se(1) and three equivalent Se(2) atoms. All Li(1)-Se(1) bond lengths are 2.56 Å. All Li(1)-Se(2) bond lengths are 3.16 Å. Mn(1) is bonded to one Se(1) and three equivalent Se(2) atoms to form corner-sharing MnSe4 tetrahedra. The Mn(1)-Se(1) bond length is 2.31 Å. All Mn(1)-Se(2) bond lengths are 2.51 Å. There are two inequivalent Se sites. In the first Se site, Se(1) is bonded to three equivalent Li(1) and one Mn(1) atom to form corner-sharing SeLi3Mn tetrahedra. In the second Se site, Se(2) is bonded in a distorted trigonal non-coplanar geometry to three equivalent Li(1) and three equivalent Mn(1) atoms.