Yoko Kuroda

Vibrational spectra of water molecules in some transition metal dichloride dihydrates

Abstract The i.r. spectra of MCl2.2H2O (M = Co, Fe, Mn) and partially and almost completely deuterated derivatives thereof were recorded at liquid nitrogen and room temperature in a low wavenumber region covering 700-200 cm−1. Librational bands were assigned unambiguously to rocking and wagging modes by taking advantage of a theoretical conclusion that the isotopic frequency ratio, v H 2 O v HDO (but not v H 2 O v D 2 O , is considerably different between the rocking mode and the wagging mode. The force constant of rocking is one order of magnitude greater than that of wagging. The result is explained by means of a simple point-charge model.

Vibrational spectra of trimethylamine oxide dihydrate

Abstract The infrared spectrum in the solid state and the polarized Raman spectra of aqueous solutions of trimethylamine oxide dihydrate have been measured. The normal vibrations of trimethylamine oxide have also been calculated using the Urey-Bradley—Shimanouchi potential function with all internal coordinates except for torsional motions. The observed frequencies have been assigned based upon the polarization properties of Raman lines and the results of the calculation. As a result an assignment by G iguere and C hin has partly been revised. The observed frequencies and the force constants show that the nitrogen atom of trimethylamine oxide is essentially tetravalent. The CN bond character is influenced by the oxygen atom which is more electronegative than a nitrogen atom.

Normal vibrations of copper (II) formate in a planar network structure

Abstract The infra-red spectra of copper (II) formate tetrahydrate, copper (II) formate tetra(deuterium oxide), copper (II) formate bisurea dihydrate, and pale blue anhydrous copper (II) formate were recorded in the range of 4000-200 cm−1. Factor group analysis was carried out with a D4a 5 model for the two-dimensional network structures of copper (II) formate constituting the crystals of the tetrahydrate. The normal frequencies of infra-red-active in-plane vibrations were calculated using a simple Urey-Bradley potential function. On the basis of the results of calculations, the observed spectra were explained, yielding the CuO stretching force constant of 0.8–1.0 mdyn/A.

Infra-red and Raman spectra of N-trimethylborazole

Abstract The infra-red and Raman spectra of N-trimethylborazole were recorded and major observed frequencies were assigned to various modes of vibration. The infra-red spectrum was found to be quite different from that reported in the literature. A possible reason for this disagreement is suggested.