The Fourier transform (FT) IR spectra of [Cl]2FeS2MoS2FeCl2]2- were measured at 100-500 cm-1. A simplified general valence force field was used in a normal coordinate anal. The calculated frequencies agreed with the observed ones, with a mean deviation of <1.0%, confirming the assignments of the vibrational spectrum. Sixteen force constants including stretching, bending, torsion, and stretching-stretching interactions were obtained. The rationality and the reliability of the results are discussed.

Key words: INFRARED SPECTROPHOTOMETRY, IRON COMPLEX, NITROGENASE, MOLYBDENUM COMPLEX, DISULFIDE, CHEMICAL BONDS, CLUSTER COMPOUND, ANION, POLYNUCLEAR COMPLEX, MATRICES