A Band Assignments and Structural Elucidation

Depolarization data on trimethylphosphine oxide are now available and the relationship between the symmetric and asymmetric POP vibrations has been equated for diphosphates, and some halogen and metal salt derivatives. The polarization of a carbonyl group produced by its conjugation with an ylide causes a large decrease in vco- This shift to lower frequency is increased further when a double bond is interposed, thus increasing the extent of conjugation. - 

spectra of two crystal forms of aminomethylphosphonic acid (91) and its and analogues have been studied. A Fermi resonance between vxh and vxd vibrations and certain binary combinations can explain most of the spectra. The related aminophosphinic acid (92) and 

Henrici-Olive and S. Olive, Angew. Chem. Internal. Edn., 1970, 9, 957. 

Berenguer, J. Castells, R. M. Galard, and M. Moreno-Manas, Tetrahedron Letters, 1971, 495. 

Garrigou-Lagrange and C. Deslrade,. /. Chim. phys., 1970, 67, 1646 C. Destradc and C. Garrigou-Lagrange, ibid., p. 2013. 

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