Structural Analysis of Dinuclear Molybdenum(V) Dibutyldithiocarbamate Complexes and Crystal Structure of Di-μ-sulfidobis [oxo(dibutyldithiocarbamato)]molybdeum(V)

Abstract

The ultraviolet, infrared and Raman spectra of. a series of oxo- and sulfido-bridged dinuclear molybdenum ( V ) complexes, (a) Mo₂O₂(μ-O, S) (dtc)₂, (b) Mo₂O₂(μ-O, S) (dtc)₂(c) Mo₂O₂(μ-S)₂ (dtc)₂ and (d) Mo₂O₂(μ-O, S)[S₂CN(n-Bu)₂] were investigated and the crystal structure of (b), which was prepared by the reaction among molybdenum(VI) oxide, sodium hydrogensulfide and dibutyldithiocarbamic acid, was solved by the 3-dimensional X-ray method using MULTAN 78 program. The crystals are triclinic, space group P1 with lattice parameters of a=11.701(2), b=13.549(3), c=9.315(3)Å, 13i, α=101.72(3), β=97.37( 4 ) and γ=87.38(2)^o for Z=2. The final R factor is O.13 for 5280 reflections.
These molybdenum complexes have characteristic and intense UV absorption maxima in the 230-280 nm region (ε_max≥3.2 ×10⁴) assigned to π→π^* transitions of ligands. The UV methodmax combined with high-performance liquid chromatography is useful for the identification and selective determination of. mixed complexes. The infrared absorption bands for functional groups were characterized as follows:ν(C=N)ca.1530^-1, ν(Mo=O)ca. 965 cm^-1, ν(Mo=S)ca.545cm^-1, ν(Mo_??_Mo) 708, 460, δ(Mo_??_Mo)541, 348cm^-1 ν(Mo_??_Mo) 470cm^-1, δ(Mo_??_Mo)335cm^-1, The Raman lines were: ν(C=N)ca. 1530cm^-1, ν(Mo=O)965 cm^-1, ν(Mo=S)545cm^-1, ν(Mo_??_Mo) 710, 461cm^-1, and ν(Mo_??_Mo) 429cm^-1The method for the identification of molybdenum complexes based on these characteristic group frequencies was discussed.