COMPUTATIONAL PREDICTION OF A GROUND-STATE TRIPLET ARYLNITRENIUM ION AND A POSSIBLE GROUND-STATE TRIPLET SILYLENE

Density functional calculations predict that bis-(2,6-di-t-butyl)pheny lnitrenium has a triplet ground state and that the corresponding silyl ene has essentially degenerate singlet and triplet states. The steric hulk of the aryl ligand strongly destabilizes the singlets in each cas e relative to the triplets; the latter can more readily accommodate la rge valence angles at the nitrogen or silicon atom. (C) 1997 Elsevier Science Ltd.