Design of three-dimensional solid-state boron oxide networks: Ab initio calculations using density functional theory

Most binary oxides are classic examples of densely packed systems; a given compound generally adopts only a small number of structures. Here for boron monoxide (BO) in contrast we demonstrate the existence of many low, equienergetic forms, consistent with the limited experimental NMR data. All are dominated by six-membered rings connected in various ways; there is considerable variation in B-O-B angles and torsion angles but not in bond lengths. The volume per formula unit of a less dense nanoporous phase is twice that of other denser forms.