ISSN:
1089-7690
Source:
AIP Digital Archive
Topics:
Physics
,
Chemistry and Pharmacology
Notes:
The excitation energies and ionization potentials of the atoms in the first transition series are notoriously difficult to compute accurately. Errors in calculated excitation energies can range from 1 to 4 eV at the Hartree–Fock level, and errors as high as 1.5 eV are encountered for ionization energies. In the current work we present and discuss the results of a systematic study of the first transition series using a spin-restricted Kohn–Sham density-functional method with the gradient-corrected functionals of Becke and Lee, Yang and Parr. Ionization energies are observed to be in good agreement with experiment, with a mean absolute error of approximately 0.15 eV; these results are comparable to the most accurate calculations to date, the quadratic configuration interaction single, double (triple) [QCISD(T)] calculations of Raghavachari and Trucks. Excitation energies are calculated with a mean error of approximately 0.5 eV, compared with ∼1 eV for the local density approximation and 0.1 eV for QCISD(T). These gradient-corrected functionals appear to offer an attractive compromise between accuracy and computational effort.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1063/1.468265
