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(NH_4)_2[Mo_2(S_2)_6]·~(8/3)H_2O的黑色晶体属于正交晶系,D_2~3-P22_12_1空间群,晶胞参数a=12.064(6)A,b=12.534(4)A,c=19.558(9)A,V=2957(3)A~3,Z=4,D_c=2.23 g·cm~(-3)。结构修正后,R=0.092,R_ω=0.072.晶体由[MO_2(S_2)_6]~(2-)二核原子簇离子、NH_4~+离子和H_2O分子组成。晶体中有两套晶体学上独立的[Mo_2(S_2)_6]~(2-)离子,其一处在一般位置,另一处在二重轴上。每一不对称单位中含有1.5个[Mo_2(S_2)_6]~(2-)离子,在[Mo_2(S_2)_6]~2-离子中,每个Mo被4个S_(2-)~2侧接配位,按变形的十二面体排列,其中的两个桥式连接于两个Mo之间,其余两个接在外端。Mo-S键长2.441A(平均),S—S键长2.049A(平均)。Mo-Mo键长2.784A(平均),与单键键长相当。Mo的形式价态为五价,很可能是MO~(lV)-Mo~(VI)混合价态,从而在颜色上产生显著特点.
The black crystals of (NH_4) _2 [Mo_2 (S_2) _6] ~ (8/3) H_2O belong to orthorhombic and D_2 ~ 3-P22_12_1 space group with unit cell parameters of a = 12.064 (6) A and b = 12.534 (4) A, c = 19.558 (9) A, V = 2957 (3) A ~ 3, Z = 4, D_c = 2.23 g · cm -3. After structure correction, R = 0.092 and R_ω = 0.072. The crystal consists of [MO_2 (S_2) _6] ~ (2-) clusters, NH 4+ ions and H 2 O molecules. There are two sets of crystallographically independent [Mo_2 (S_2) _6] ~ (2-) ions in the crystal, one in the normal position and the other on the double axis. There are 1.5 [Mo_2 (S_2) _6] ~ (2-) ions in each asymmetric unit, and every Mo in [Mo_2 (S_2) _6] Side-by-side coordination, according to the deformation of the dodecahedron arrangement, one of the two bridges connected between the two Mo, the other two connected to the outer end. Mo-S bond length 2.441A (average), S-S bond length 2.049A (average). Mo-Mo bond length 2.784A (average), and a single bond length equivalent. The valence state of Mo is valence, which is likely to be MO ~ (lV) -Mo ~ (VI) mixed valence state, which has significant characteristics in color.