Table 2. Atomic positions of a 16-atom orthorhombic unit cell.

Atomic position	x	y	z
1	0	0	0
2	1/2	0	0
3	1/4	1/2	0
4	3/4	1/2	0
5	0	1/3	1/2
6	1/2	1/3	1/2
7	1/4	5/6	1/2
8	3/4	5/6	1/2
9	0	0	3/8
10	1/2	0	3/8
11	1/4	1/2	3/8
12	3/4	1/2	3/8
13	0	1/3	7/8
14	1/2	1/3	7/8
15	1/4	5/6	7/8
16	3/4	5/6	7/8