Correlation of 95Mo NMR chemical shifts, electronic absorption bands, and solvent donor numbers for some dimeric Mo2(O2CR)4L2 solvent adducts

Autor: José Campo, Elmer C. Alyea
Rok vydání: 1998
Předmět:
Zdroj: Polyhedron. 17:275-279
ISSN: 0277-5387
DOI: 10.1016/s0277-5387(97)00319-7
Popis: The 95Mo NMR chemical shifts are reported for two series of solvent adducts of the dimeric molybdenum(II) complexes Mo2(O2CR)4L2 (R = CF3, But; L - solvent). The large deshielding effect (over 450 ppm for the R = CF3 series as the solvent changes from chloroform to hexamethylphosphoramide) correlates well with the donor number of the solvent. The lowest energy electronic absorption band corresponding to the δ−δ* transition also moves to longer wavelength with the more strongly coordinating solvents, which is consistent with weakening of the MoMo quadruple bond and the dominance of the ΔE parameter in the paramagnetic term which controls the magnitude of δ(95Mo).
Databáze: OpenAIRE