Vibrational spectra and crystal structure of 2,2′-bifurane

Abstract

The infrared and Raman spectra of 2,2′-bifurane in the liquid and solid state have been measured between 4000 and 50 cm −1. Infrared spectra in polarized light have been obtained at 85°K on oriented polycrystalline samples. The observation of two different crystal faces allowed to identify all the Davidov components. Splitting of the normal modes was also observed for most of the Raman active fundamentals. The molecules have been found to be trans planar in the crystal and to assume different conformations in the liquid. The data obtained from the crystal spectra are consistent with an orthorhombic factor group with four molecules located at C i sites. An almost complete assignment of the fundamentals is also reported.