Infrared and Raman spectra of some complexes between thiourea and tellurium(II). Part II

The laser-excited Raman spectra of a number of solutions of tellurium complexes containing substituted thioureas as donors have been recorded. It has been possible to confirm the assignments proposed in the first part of this work, viz. the symmetric Te–S stretching vibration frequency is about 230 cm.–1. Examination of a range of solid samples both in the Raman effect and in absorption adds further support to this proposal and leads to the suggestion that ΔνCl–Te–Cl occurs near 245, ΔνBr–Te–Br at 150 and ΔνI–Te–I at 110 cm.–1 whereas in the i.r. the analogous values are 205, 160, and 130 cm.–1. The values and their significance are briefly discussed.