Valence band structure and decay process in the inner-shell excitation of boron oxide

The electronic structure and radiative/non-radiative decay processes in the inner-shell excitation of B2O3 were investigated using soft x-ray emission and photoelectron spectroscopy. Based on density of states calculations, t he electronic structure of B2O3 as probed by m-ray emission spectroscopy (X ES) and photoelectron spectroscopy (PES) arises from hybridized sp(2)-plana r B-O bonding in B-Os triangular units. A fairly nondispersive band structu re was also suggested by excitation energy-dependent XES. XES and PES indic ated both a resonant radiative decay process and a resonant non-radiative d ecay process with pi* excitation at the B K threshold. A small resonant rad iative decay peak was observed with pi* excitation at the O K K threshold, probably due to a more weakly bound pi* state at the O K threshold than at the B K threshold. Copyright O 1999 John Wiley & Sons, Ltd.