B. Ruscic, B. Kovac, L. Klasinc, and H. Gusten, Z. Naturforsch. 33a, 1006-1012 (1978)

Photoelectron Spectroscopy of Heterocycles. Fluorene Analogues

B. Ruščić,^a B. Kovač,^a L. Klasinc,^a and H. Güsten^b

^a Rugjer Bošković Institute, Zagreb, Croatia
^b Institut für Radiochemie, Kernforschungszentrum Karlsruhe, Karlsruhe, Germany

Z. Naturforsch. 33a(9), 1006-1012 (1978)

The He(I) photoelectron spectra of fluorene, and its analogues, biphenyl, dibenzofuran, carbazole, dibenzothiophene, and phenanthrene were measured and analyzed. The assignment of the π-electron ionizations using orbital interaction and symmetry arguments for the constituent parts of the molecules indicates that the energy levels of the fluorene analogues can be reproduced within a few percent of error. A close linear correlation between the π-ionization energies and the eigenvalues of the corresponding HMO-orbitals is obtained as well.