Fig. 1.

Crystal structure of I4/mcm(00γ) commensurate analogue with γ = 4/3. The supercell is build up of 3 body-centered tetragonal cells with atoms at Wickoff position 8h(x,x + 1/2,0) (host), and 4 C-face-centered tetragonal cells with atoms at positions (0, 0, 0) and (1/2,1/2,0) (guest). The overall structure is a body-centered tetragonal lattice described by space group I4/mcm with 32 atoms at Wickoff positions 4c (0, 0, 0), 4a(0,0,1/4), 8h(x,x + 1/2,0), and 16l(x,x + 1/2,1/3). After structure optimization the positions of atoms in the host sub-lattice deviate from the initial one.