SB12 is Modderite-like structured and crystallizes in the trigonal R-3m space group. There are two inequivalent B sites. In the first B site, B(1) is bonded in a 6-coordinate geometry to two equivalent B(1), three equivalent B(2), and one S(1) atom. In the second B site, B(2) is bonded in a 6-coordinate geometry to three equivalent B(1) and three equivalent B(2) atoms. S(1) is bonded in an octahedral geometry to six equivalent B(1) atoms.
SB12 is Modderite-like structured and crystallizes in the trigonal R-3m space group. There are two inequivalent B sites. In the first B site, B(1) is bonded in a 6-coordinate geometry to two equivalent B(1), three equivalent B(2), and one S(1) atom. Both B(1)-B(1) bond lengths are 1.74 Å. There are two shorter (1.74 Å) and one longer (1.78 Å) B(1)-B(2) bond length. The B(1)-S(1) bond length is 2.37 Å. In the second B site, B(2) is bonded in a 6-coordinate geometry to three equivalent B(1) and three equivalent B(2) atoms. There is one shorter (1.68 Å) and two longer (1.85 Å) B(2)-B(2) bond lengths. S(1) is bonded in an octahedral geometry to six equivalent B(1) atoms.