I. Novak et al., ELECTRONIC-STRUCTURE OF THIOPHENES WITH MIXED SUBSTITUENTS, Journal of electron spectroscopy and related phenomena, 63(1), 1993, pp. 85-90
He I photoelectron spectra of title compounds were recorded and assign
ed by MNDO-PM3 calculations and comparison with spectra of related der
ivatives, Substituents were found to noticeably affect the electronic
structure, depending on their type and position of attachment to the r
ing. MNDO-PM3 calculation results become unreliable in cases of thioph
enes with widely different substituent types.