Author(s)

Marco Meibohm, Hans Hermann Otto^*

Materials Science and Crystallography, Technical University of Clausthal, Clausthal-Zellerfeld, Lower Saxony, Germany.

Orthorhombic copper polysilicate, CuSiO₃, is isotypic to the spin-Peierls compound CuGeO₃ and represents a further example of a quasi-one-dimensional spin = 1/2 antiferromagnetic Heisenberg chain system. This is a representation of the first Raman and IR/FIR spectra for CuSiO₃, measured at room temperature on polycrystalline samples. A comparison of the optical phonons, predicted by a factor group analysis, with those observed for the CuGeO₃ prototype, is presented. A mode assignment for the silicate is given. Surface effects due to a very small crystallite size may cause additional broad bands observed in the Raman spectrum of CuSiO₃. From the analysis of the Davydov doublet an intralayer-to-interlayer bond strength of about 40 is derived for the silicate, which is about 20% lower than for the isotypic germanate, allowing for different magnetic responses at low temperature.

IR/FIR Spectra, Raman Spectra, Factor Group Analysis, Davydov Analysis, Copper Polysilicate, CuSiO₃, Copper Polygermanate, CuGeO₃, Low-Dimensional Compounds, Spin-Peierls Transition

Meibohm, M. and Otto, H. (2018) Comparison of the Vibrational Spectra of Copper Polysilicate, CuSiO₃, with Those of the Prototypic Copper Polygermanate, CuGeO₃. American Journal of Analytical Chemistry, 9, 311-321. doi: 10.4236/ajac.2018.96024.