Isomer shift , dithiocarbamate complexes

The Sn Mossbauer spectra of a number of tin dithiocarbamate complexes have been reported (89, 91, 94, 108, 118, 147, 178, 180) Data are collected in Table IV. The Mossbauer spectral parameters have been used to infer the coordination number of the Sn atom. The isomer shift (IS) of tin species decreases as the i-electron density at the Sn atom decreases thus the isomer shift would generally be expected to decrease on increasing coordination number or increasing electronegativity of the ligands. These two factors are difficult to separate, since the anisobidenticity of dithiocarbamate ligands generally decreases as the Lewis acidity of the metal moiety increases. 

Examination of Table IV shows no reliable correlation of the isomer shift with coordination number in organotin dithiocarbamate complexes. 

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