Lu S, Zheng Y, Yu R, Peng Y, Wu Q, Huang J
State Key Laboratory of Structural Chemistry, Fujian Institute of Research on the Structure of Matter, Chinese Academy of Sciences, 350002 Fuzhou.
Guang Pu Xue Yu Guang Pu Fen Xi. 2000 Dec;20(6):751-4.
By combining the results of IR spectroscopic experiments with the molecular structures, the main stretching vibrations of a series of the heterometallic tetranuclear cluster compounds with [M3YS3M'] cluster core (M = Mo, W; Y = O, S; M' = Cu, Sn, Pb, Sb, Bi) have been assigned. The characteristic features and the bonding situations of the five configuration types are discussed. It is shown from the IR and Raman spectra that when M' is a transition metal such as Cu, the nu M's frequency of the [M3YS3M'] core has a value comparable to that of corresponding M'-S covalent bond thus indicating a close combination of M' with [M3YS3]. Whereas when M' is a main group metal, the nu M'-s vibration is always observed in a lower region than of the M'-S covalent bond because of a loose combination of M' with[M3YS3]. However, remarkable enhancement of M-M band strength due to the addition of M' is demonstrated by Raman spectra. Some comments for the M-M vibration of various structures of these compounds are also described.
