Abstract
There are six possible configurations for CH3-X-X-CH3 (X=0, S, Se, Te); D3d, D3h, C2h, C2v, C2 and C1. So the structures of molecules of the type CH3-X-X-CH3 have been the subject of several investigations. It has been reported that CH3-X-X-CH3 type molecules had a skewed structure with C2 symmetry or a cis form with C2v symmetry. However the obtained vibrational spectra show the general simplicity of the spectra and the lack of coincidence between Raman and infrared frequencies which indicates that a molecule has a center of symmetry. Therefore a C2 structure or a C2v symmetry can not be supported for CH3-X-X-CH3 type molecules. The present object of the vibrational study is to distinguish between the six most probable structures.