Electronegativities, from Mossbauer spectroscopy

Mossbauer spectra of a series of Sn(Pc)X2 have been studied. The linear relationship between the isomer shift and the axial ligand electronegativity is interpreted in terms of an electron density increase on the Sn atom and a decrease in n donation from Pc to Sn with an increase in axial tr donation.198 This is supported by X-ray photoelectron spectroscopy. 

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