We present vibrational spectra of three stable, well-reproducible, polymorp
hic forms of cimetidine (cim), a drug which is a powerful histamine Hz-rece
ptor antagonist used in the treatment of peptic ulcer and the Zollinger-Ell
ison syndrome. Assignments of Raman and IR bands are made using semiempiric
al methods: MNDO, AM1 and PM3. We also describe the synthesis of Me(cim)(2)
(ClO4)(2), where Me = Cu(ZI), Cd(II), Co(II) and Ni(LI), and present their
vibrational data. We show that the obtained complexes are isostructural, ho
wever a metal ion that occupies a center of octahedral unit introduces some
distortions that can be seen in the spectra, We also make tentative assign
ment of metal-ligand stretching modes observed in low frequency range. (C)
1999 Elsevier Science B.V. All rights reserved.