The force field of 4-vinylpyridine and 4-vinylpyridine metal complexes

A normal coordinate analysis is carried out to obtain the Urey-Bradley forc e constants for 4-vinylpyridine (4-vipy) assuming under C-2v. point group. These constants are adjusted to fit the observed frequencies for 4-vipy and its deuterated species. The calculated frequencies are found to reproduce well experimental infrared spectrum of liquid 4-vipy. Two new Hofmann-T-d-type complexes of the form Cd (4-vipy)(2) M (CN)(4) (M = Cd, Hg) have been prepared and their infrared spectra are reported. The c oordination effect on the ligand vibrational modes was also investigated. I t is shown that the ring vibrations in pyridine are to be effected upon met al substitution. (C) 2001 Elsevier Science B.V. All rights reserved.