A study of the electronic structure of the hexafluorobenzene and pentafluorobenzene molecules by ultrasoft X-ray emission spectroscopy

The electronic structure of the hexafluorobenzene and pentafluorobenzene molecules was studied by ultrasoft X-ray emission spectroscopy. The FK _α and CK _α spectra of these compounds in the gas phase were obtained. The results of quantum-chemical calculations performed at the RHF/STO-6G//6-31G level were used to construct the theoretical spectra. The highest occupied molecular orbitals were found to consist largely of the 2p _π carbon atomic orbitals. The contribution of fluorine orbitals was small. π-Type interactions mainly involved deeper valence orbitals.