VIBRATIONAL SPECTROSCOPIC STUDY OF [(CH3-)2P(O)2]- AND [(R-)2P(O)2]

ir and Raman data for sodium dimethylphosphinate, [CH3-)2P(O)2]Na, were obtained and used to assign the vibrational spectrum of the [CH3-)2P(O)2]- anion. Comparison of [CH3-)2P(O)2]Na, with the K analog in the solid phase shows that some ir bands at low frequency result from lattice vibrations. Our data suggest that the [CH3-)2P(O)2]- anion in aqueous solution has C2v symmetry and, in the solid phase, this anion has C2v site symmetry. Correlations of the ir bands resulting from v(antisym. and sym. PO2) vibrations with structures [(R-)2P(O)2]- are also given. © 1968.