VIBRATIONAL-SPECTRA AND STRUCTURES OF ZINC CARBOXYLATES I - ZINC ACETATE DIHYDRATE

The crystal structure of zinc acetate dihydrate was re-refined by X-ra y diffraction analysis of the single crystal. The monoclinic cell dime nsions were revised as a = 14.394 (3), b = 5.330 (2), c = 10.962 (3) A ngstrom and beta = 99.8 (2)degrees with Z = 4. The bond distances and bond angles were also refined. Based on the structure, a normal mode a nalysis was made and the valence force constants were determined. Prec ise spectral assignments were made. Based on the assignments and the s tructure, the relation between the coordination forms and the vibratio nal frequencies of the carboxylate antisymmetric stretch and the symme tric stretch were discussed. In order to identify the coordination for m of the carboxylate group from the vibrational frequencies, we propos e the importance of other carboxylate modes other than the stretches. (C) 1998 Elsevier Science B.V. All rights reserved.