Knowledge Bank

“Three successively improved MO wave functions for $N2$ are compared. In addition to the usual physical propertied and the Mulliken population analysis, contour diagrams of the molecular Orbital wave functions, total charges density and the function $\delta \rho (R)=\rho M(R)-\rho A(R)$ are considered. $\rho M(R)$ is the molecular charge density and $\rho A(R)$ is the density of the constituent atoms, superimposed at the molecular internuclear distance. The study of $\delta \rho (R)$ has been suggested by Roux and $Daudel1$ and $Ruedenberg.2$ While the improvement in the wave functions causes severe difficulties with the population analysis result, there is a sizeable change in some features in $\delta \rho (R)$ toward a (perhaps) more satisfactory picture of the bond charge density. By changing the ``valence state’’ of the constituent atoms, $\rho A(R)$ changes also. An optimum $2s-2p\sigma$ hybridization may be found which minimizes$|\delta \rho (R)|$.$\mathrm{<mrow\; data-mjx-texclass="ORD">2</mrow>}$ Some comparisons are made with other similar diatomic molecules.”