Electronic spectra and structure of aromatic derivatives of the group IVB and group VB elements

Abstract

1. There is a regular increase in the energy of the lowest singlet and triplet excited levels in the aromatic derivatives of the elements C, Si, Ge, Sn and N, P, As, Sb, Bi, which is consistent with the quantum-mechanical model of the mixing of the electronic states of the aromatic system with states involving p and s orbitals of the heteroatom with different energies and symmetries. 2. The yields of the radiative electronic transitions regularly decrease, and the probabilities of nonradiative intramolecular electronic transitions increase. 3. The temperature effects inthe 300–77°K range in the electronic absorption spectra have been found and are associated with a postulated change in the spatial configuration of the compounds investigated.