若干线型Mo-Fe-S簇合物红外光谱及其与结构关系的研究

对若干线型Mo一Fe一S簇合物Cl2FeS2MoS2FeCl2]-2](1)、S2MoS2FeCl2]^2^-(2)、S2MoS2Fe(SPh)2]2-](3)、S2MoS2FeS2Fe(SPh)2]3-](4)、S2MoS2FeS2MoS2]3-](5)、Cl2FeS2FeCl2]2-](6)、(PhS)2FeS2Fe(SPh)2]2-](7)的红外光谱进行了研究。通过比较它们的特征频率、结构参数和金属原子的氧化态,对νMo-St、νMo-SbνFe-Sb、νFe-SPh、νFe-Cl进行了归属。并对δS-Mo-S的归属作了初步探讨。文中讨论了MoS2Fe单元中Mo原子对νFe-Sb的影响, 通过振动频率与结构关系的研究揭示其内在联系及规律性。对两条途径的亲电诱导效应进行了讨论, 并提出一个能定性标志Fe→Mo电荷迁移大小的有用参数Δν值。

Studies on the IR spectra of some linear Mo-Fe-S clusters and the relationship between the spectra and their structure

The IR spectra of some linear Mo-Fe-S clusters Cl2FeS2MoS2FeCl2]2-, S2MoS2FeCl2]2-, S2MoS2Fe(SPh)2]2-, S2MoS2FeS2Fe(SPh)2]3-, S2MoS2FeS2.MoS2]3-, Cl2FeS2FeCl2]2-, and (PhS)2FeS2Fe(SPh)2]2- were investigated. The characteristic frequencies nMo-St, nMo-Sb, nFe-Sb, nFe-SPh, nFe-Cl were assigned by comparing their vibrational frequencies, structural parameters and oxidation states of metal in these clusters. The assignment of dS-Mo-S was attempted. The influence of Mo atom on nFe-Sb in the clusters containing the heteronuclear MoS2Fe unit and the electrophilic induced effect in a different way are discussed. The internal relationship and regularity between the characteristic frequencies and some structural parameters were demonstrated. Finally a valuable parameter Dn, which may be taken as a qual. estimate of the extent of Fe ?Mo charge transfer in Mo-Fe-S clusters, is proposed.