A localized molecular orbital study of the structure and bonding of ozone

The loca lized molecular o rbital theory and energy partiti on ing formali sm have been invoked to study the structure and bonding in ozone molecule. The range of in vestigati o n covers a large number o f conformations generated theore ti cally over the w ide range of apical angles between angular (C21.) to linear (0 =11 ) shapes. The results demonstrate that. s imilar to the bonding in diborane, the re are two equi valent three-cente red bonds in ozone embracing three oxygen atoms in all the conformations. The possibility of a triangu lar struc ture of ozone is ruled out because the computed locali zed mo lecular orbitals demonstrate that there is no bonding between the termin al oxygen atoms and the decomposed e nergy component s show that the inte raction be tween terminal oxygen atoms is strong ly repul s ive. Charge density di stribution is asy mmetric in the homonuclear molecule and its dipole moment is an al gebraic sum of bond moment and lone pair mo ment and lone pair on the apical oxygen ato m contributes significantl y to the dipo le mo ment. It is demonstrated that any atlempt of calculating the apical angle from the ex perimentall y determined dipole moment would be e rroneous and mi slead ing. Variation of dipole moment as a function of angular to linear reorgani za tion of mo lecular shape is corre lated in terms of computed quantum mec hanical hybridi zat ion of the lone pair on the apical oxygen a tom. The barrier to in vers ion of ozone th rough the linear (0=1, ) transiti on state originates from a subtle inte rplay of oneand twocente r energy components over the ent ire skeleton of the molecule.