Journal of Physical Chemistry A, Vol.120, No.48, 9607-9611, 2016
Fundamental Aspects of Recoupled Pair Bonds. III. The Frustrated Recoupled Pair Bond in Oxygen Monofluoride
In a previous paper in this series, we discussed the formation of recoupled pair bonds in the a(4)Sigma(-) states of CF and SF in which the recoupling process was essentially complete at the equilibrium geometry of the molecule. In this paper, we examine the a(4)Sigma(-) state of oxygen monofluoride (OF), which could also have a recoupled pair bond. Unlike the other two molecules, generalized valence bond calculations predict that the recoupling in OF is woefully incomplete at R-e and the resulting potential energy curve for the OF(a(4)Sigma(-)) state is purely repulsive; the binding energy, approximate to 11 kcal/mol, is entirely due to dynamical correlation. A number of factors account for these differences, but the nature of the dominant correlation effect in the oxygen 2p lone pair as well as the spatial extent of the 2p orbital are paramount.