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对含有[MS4]2-（M＝Mo，W）单元的一系列钼（钨）-钼-硫簇合物进行了95MoNMR研究，定性分析了95Mo化学位移随金属原子配位数、配位金属种类和配位金属配体改变而变化的规律。结果表明，随着[MoS4]2-配位金属原子数的增加，[MoS4]2-上Mo的化学位移逐渐向高场移动，这可归因于低氧化态MO0上的电子通过硫桥离域到高氧化态的Mo上。为了解析Mo0上化学位移的实验结果，采用MM＋力场对[（OC）4MOS2MoS2]2-和[｛（OC）4Mo｝MoS4]2-的晶体结构进行几何优化，使之更接近于溶液中的结构，然后利用Fenske－Hall方法计算Mo原子上的净电荷分布，计算结果较好地好择了Mo和Mo0化学位移的变化趋势。
A series of molybdenum (tungsten) -molybdenum-sulfur cluster complexes containing [MS4] 2- (M = Mo, W) units were studied by 95M NMR. The chemical shifts of 95Mo groups were calculated with the coordination number of metal atoms, Species and coordination metal ligand changes and changes in the law. The results show that the chemical shift of Mo on [MoS4] 2- gradually shifts to high field with the increase of the number of [MoS4] 2-coordination metal atom, which can be attributed to the fact that electrons in low oxidation state MO0 are separated by sulfur bridges Mo to the high oxidation state. In order to analyze the experimental results of chemical shifts on Mo0, the crystal structure of [(OC) 4MOS2MoS2] 2- and [{(OC) 4Mo} MoS4] 2- was optimized by MM + Structure, and then calculate the net charge distribution on the Mo atom by Fenske-Hall method. The calculated results better select the change trend of Mo and MoO chemical shifts.