Metal Isotope Effects on the Vibrational Spectra of Polymeric Metal Complexes. III. Infrared Spectra of [Bis (L-asparaginato) zinc (II)]_n

Abstract

The infrared spectra of [bis (L-asparaginato) zinc (II)]_n and its isotopic complexes containing ⁶⁴Zn, ⁶⁸Zn and deuterium have been measured in the region between 4000 and 200 cm^-1. By referring to the isotope frequency shifts, three bands at 301, 265 and 244 cm<-1> have been assigned to Zn-ligand stretching vibrations caused from coupling among Zn-O and Zn-N stretching vibrations. The frequency range of the Zn-O stretching vibrations suggests that the Zn-O binding force of zinc-amino acids is probably larger than has been considered.