NEW ORGANIC POLYMER PRECURSORS - SYNTHESIS AND ELECTRONIC-STRUCTURE OF THIENYLPYRIDINES AND THIENYLETHYNYLPYRIDINES

He I and He II UV photoelectron spectra (UPS) of isomeric thienylpyrid ines and thienylethynylpyridines have been recorded. Their electronic structures were analysed and spectra assigned on the basis of He II/He I intensity variations, comparison with UPS of pyridine, thiophene an d ethyne and semiempirical MO calculations. The spectra indicate that there is considerable interaction between pi orbitals of thiophene, py ridine and ethynyl moieties. The relationship between electronic struc ture and formation of novel polymer materials is discussed.