Molecular calculations of excitation energies and „hyper...polarizabilities with a statistical average of orbital model exchange-correlation potentials
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چکیده
An approximate Kohn–Sham exchange-correlation potential nxc SAOP is developed with the method of statistical averaging of ~model! orbital potentials ~SAOP! and is applied to the calculation of excitation energies as well as of static and frequency-dependent multipole polarizabilities and hyperpolarizabilities within time-dependent density functional theory ~TDDFT!. nxc SAOP provides high quality results for all calculated response properties and a substantial improvement upon the local density approximation ~LDA! and the van Leeuwen–Baerends ~LB! potentials for the prototype molecules CO, N2 , CH2O, and C2H4 . For the first three molecules and the lower excitations of the C2H4 the average error of the vertical excitation energies calculated with nxc SAOP
منابع مشابه
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تاریخ انتشار 1999