The electronic structure of a diarsaallene –AsyCyAs– and a phosphaarsaallene –PyCyAs–: UV photoelectron spectroscopy and theoretical studies

The electronic properties of a diarsaallene ArAsyCyAsAr and a phosphaarsaallene ArPyCyAsAr (Ar: 2,4,6-tri-tert-butylphenyl) have been investigated by using UV photoelectron spectroscopy and by density functional calculations on model compounds [(CH3)2 C6H3PnyCyAsC6H3(CH3)2, Pn: As, P]. Moreover, a comparison of the geometrical and electronic structures of the parent heteroallenes with those of the arsaethene H2CyAsH and phosphaethene H2CyPH has also been undertaken in order to determine the magnitude of the interaction between the p bond and the pnictogen lone pair nPn. q 2003 Elsevier B.V. All rights reserved