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Derivation of a formula for the resonance integral for a nonorthogonal basis set
Abstract:
In a self-consistent field calculation, a formula for the off-diagonal matrix elements of the core Hamiltonian is derived for a nonorthogonal basis set by a polyatomic approach. A set of parameters is then introduced for the repulsion integral formula of Mataga-Nishimoto to fit the experimental data. The matrix elements computed for the nonorthogonal basis set in the pi-electron approximation are transformed to those for an orthogonal basis set by the Löwdin symmetrical orthogonalization.
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