LiZn_{4 − <i>x</i>}(<i>x</i>= 0.825) as a (3 + 1)-dimensional modulated derivative of hexagonal close packing

Abstract

The (3+1)-dimensional modulated structure of the LiZn(4 - x) (x = 0.825) binary compound has been determined in the superspace. The compound crystallizes in the orthorhombic superspace group Cmcm(α00)0s0 with a = 2.7680 (6), b = 4.7942 (6), c = 4.3864 (9) Å, modulation wavevector: q ≃ 4/7a*. The structure is a derivative from the hexagonal close packing. The cubo-octahedron as a coordination polyhedron (c.n. = 12) is typical for all atoms. Bonding between atoms is explored by means of the TB-LMTO-ASA program package. The absence of strong interatomic interactions in LiZn(4 - x) is the main reason for the possible structure transformations.