AM1 STUDY OF PHOTOELECTRON-SPECTRA .9. 6-TETRACHLORO-2,2-DIHYDRO-1,5,2-DIAZAPHOSPHORININE

The pi-orbital structure of the monomeric form of the 2,2,4,6-tetrachl oro-2, 2-dihydro-1,5,2-diazaphosphorinine has been studied by photoele ctron spectroscopy and using quantum-chemical calculations by the semi empirical AM1 method. It has been concluded that the electronic and en ergy characteristics of four higher pi-MOs (frontier and three next or bitals) of this compound may be interpreted in terms of semipolar bond s formed by three atoms (C, P, and N). For describing two low-lying pi -MOs of the sigma(4),lambda(5)-phosphorine studied, it is necessary to take into account the pi-sigma-interaction.