In homonuclear diatomic molecules

MO wave functions in the above form give equal importance to covalent and ionic structures, which is unrealistic in homonuclear diatomic molecules like H2. This should be contrasted with (/>Vb> which in its simple form neglects the ionic contributions. Both and i//MO are inadequate in their simplest forms while in the VB theory the electron correlation is overemphasized, simple MO theory totally neglects it giving equal importance to covalent and ionic structures. Therefore neither of them is able to predict binding energies closer to experiment. The MO theory could be... 

Fig. 1. Occupied canonical MO s in homonuclear diatomic molecules. Scale in this and subsequent figures in Bohr radii.

Fig. 2. Schematic diagrams of occupied canonical MO s and the corresponding localized MO s in homonuclear diatomic molecules. The number of doubly occupied valence orbitals is denoted by n... 

Jeyes, S.R., McCaffery, A.J. and Rowe, M.D. (1978). Energy and angular momentum transfer in homonuclear diatomic molecules from polarized laser fluorescence, Mol. Phys., 36, 845-867. 

D N2) was determined as 9 79, 7 90, 7 42, 6 23, or 5-76 eV according to the assumed states of excitation of the nitrogen ion and the nitrogen atom produced. Spectroscopically obtained values for Z)(N2) are 9 76 or 7 38 eV, depending on the assumptions made. The retarding potential and appearance potential measurement alone is satisfactory for the interpretation of electron impact processes in homonuclear diatomic molecules, where there can be no doubt about the mass number of the ions. Possible confusion for heteronuclear diatomic molecules is not likely to be very great, but the method by itself is clearly inapplicable to dissociative ionization processes in polyatomic molecules, where the number of possible products is large. 

Molecular orbitals in heteronuclear diatomic molecules. 167-175 in homonuclear diatomic molecules, 160-166 of metallocenes. 670-673 in octahedral complexes. 414-418... 

A study of the contributions of the individual molecular orbital densities to the total force exerted on a nucleus in homonuclear diatomic molecules was made by Bader et al. (1967a). This study shows that the atomic polarizations binding the nuclei in these molecules do not arise primarily from the IcTg and l(Tu molecular orbitals whose densities correspond to slightly polarized Is-like atomic distributions. Indeed, in C2 these orbital densities exert small antibinding forces on the nuclei. It is the density of the 2atomic forces which bind the nuclei, while the densities of the 2cr and 3cTg orbitals are responsible for the oppositely directed atomic first moments. 

In homonuclear diatomic molecules (in which both atoms are the same, as in H2 and CI2), the electrons are shared equally between the two atoms, and the covalency is nearly ideal for such molecules. 

The simple molecular orbital theory of bonding in homonuclear diatomic molecules can be used to estimate the electron affinities of clusters. In these cases, there can be different geometries. The Cn clusters have been studied most extensively. In the case of the triatomic molecules, there are now two distances and one angle that... 

You will recall that in homonuclear diatomic molecules, orbitals that were unchanged by inversion through the centre of symmetry were labelled g and those that were changed were labelled u. Orbitals of all molecules with a centre of symmetry can be labelled using g or u subscripts. 

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