AN INFRARED SPECTROSCOPIC STUDY OF CRYSTALLINE COPPER (II) PROPIONATEAND BUTYRATE

The vibrational spectra of crystalline anhydrous copper (II) propionat e and butyrate were studied by FT-IR spectroscopy. A detailed assignme nt of the spectra of both compounds is presented and discussed. It is shown that the presence of two non-equivalent sets of carboxylate liga nds within the crystals gives rise to several band splittings, which a re particularly evident in those bands ascribable to normal modes invo lving predominantly the -C(beta)H3 or -C(beta)H2-fragments. In additio n, the vibrational assignments made for the studied molecules are show n to be very useful to help understanding the much more complex spectr a of long chain copper carboxylates.