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本文所研究的化合物系黑色准八面体晶体。晶体的空间群为I4_1/a;晶胞参数:a-22.885(10),c=25.407(7)。ρ_(obs)=2.07克/厘米~3,P_(calc)=2.126克/厘米~3。在CAD-4四圆衍射仪上,用MoK_α射线收集到I≥3σ的1621个独立衍射点的衍射强度数据。晶体结构借助三维Patterson函数解出,最小二乘方精修,偏离因子R=0.056。结果表明,晶体结构由三核钼簇阴离子和围绕着它的三个平面状阳离子构成。阴离子中,三个钼原子由两个μ_3-S桥和三个μ_2-Cl桥联结在一起,每个Mo原子另外再和两个Cl原子配位。如果撇开Mo-Mo之间的作用,则每个Mo原子周围的配位体可看成八面体排布。然而,化合物的反磁性及Mo-Mo原子间距(2.55,2.64,2.65)都显示出Mo-Mo键的特征。
The compounds studied in this paper are black quasi-octahedral crystals. The space group of the crystal is I4_1 / a; unit cell parameters: a-22.885 (10), c = 25.407 (7). ρ obs = 2.07 g / cm 3, P calc = 2.126 g / cm 3. On the CAD-4 four-circle diffractometer, the diffraction intensity data of 1621 independent diffraction spots with I≥3σ were collected by MoK_α ray. The crystal structure is solved by means of the three-dimensional Patterson function, least squares refinement, with a deviation factor of R = 0.056. The results show that the crystal structure consists of trinuclear molybdenum anions and three planar cations surrounding it. In the anions, three molybdenum atoms are linked together by two μ_3-S bridges and three μ_2-Cl bridges, each Mo atom additionally coordinating with two Cl atoms. Leaving aside the role of Mo-Mo, the ligands around each Mo atom can be considered as octahedral arrangements. However, the diamagnetic properties and Mo-Mo atomic distances (2.55, 2.64, 2.65) both show the Mo-Mo bond character.