Elemental orbital potential energies

Atomic number Element Orbital potential energy (el/) ... 

So far we have looked at molecular orbitals in a simplified way as electron pairs that try to seek locations of minimum potential energy. Now that double bonds are under consideration, it will pay us to examine in greater detail the characteristics of both atomic and molecular orbitals. You recall that an atomic orbital is a volume element oriented with respect to the nucleus of the atom where there is a high probability of finding (at the most) two electrons that are identical in quantum numbers except for direction of spin. The orbital of each type of electron (5, p, [Pg.134]

Offenhartz PO D (1970) Atomic and molecular orbital theory. McGraw-Hill, New York, p 325 (these matrix elements are zero because the AO functions belong to different symmetry species, while the operator (kinetic plus potential energy) is spherically symmetric... 

Rates for nonradiative spin-forbidden transitions depend on the electronic spin-orbit interaction matrix element as well as on the overlap between the vibrational wave functions of the molecule. Close to intersections between potential energy surfaces of different space or spin symmetries, the overlap requirement is mostly fulfilled, and the intersystem crossing is effective. Interaction with vibrationally unbound states may lead to predissociation. 

Bussery-Honvault B, Moszynski R (2006) Ab initio potential energy curves, transition dipole moments, and spin-orbit coupling matrix elements for the first twenty states of the calcium diatom. Mol Phys 104 2387-2402... 

Because atomic titanium has low-lying electronic excited states, potential energy surfaces of Ti compounds, especially unsaturated compounds, often cross. When such crossings occur, nonradiative transitions can occur via spin-orbit coupling. In such cases, spin-orbit coupling probabilities must be evaluated. Such calculations usually are performed with MCSCF-based wavefunctions. In addition, relativistic effects can have a significant effect on chemical properties, even for compounds containing elements in the first transition series. Fortunately, new models have been developed to treat relativistic effects for all-electron basis sets... 

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