Highly correlated systems. Excitation energies of first row transition metals Sc--Cu

Journal Article · Sat Jul 15 04:00:00 EDT 1989 · J. Chem. Phys.; (United States)

DOI:https://doi.org/10.1063/1.457230· OSTI ID:6067023

Raghavachari, K; Trucks, G W

The low-lying /ital d//sup /ital n/s//sup 2//r arrow//ital d//sup /ital n/+1//ital s//sup 1/ excitation energies of the first row transition metal atoms Sc--Cu are calculated using fourth-order M/congruent/ller--Plesset perturbation theory (MP4) as well as quadratic configuration interaction (QCI) techniques with large /ital spd/ and /ital spdf/ basis sets. The MP4 method performs well for Sc--Mn but fails dramatically for Fe--Cu. In contrast, the QCI technique performs uniformly for all excitation energies with a mean deviation from experiment of only 0.14 eV after including relativistic corrections. /ital f/ functions contribute 0.1--0.4 eV to the excitation energies for these systems. The highly correlated /ital d//sup 10/ state of the Ni atom is also considered in detail. The QCI technique obtains the /ital d//sup 9//ital s1//r arrow//ital d10/ splitting of the Ni atom with an error of only 0.13 eV. The results show that single-configuration Hartree--Fock based methods can be successful in calculating excitation energies of transition metal atoms.

• Research Organization: ATandT Bell Laboratories, Murray Hill, New Jersey 07974(US)
• OSTI ID: 6067023
• Journal Information: J. Chem. Phys.; (United States), Journal Name: J. Chem. Phys.; (United States) Vol. 91:2; ISSN JCPSA
• Country of Publication: United States
• Language: English

Related Subjects

640302* -- Atomic
Molecular & Chemical Physics-- Atomic & Molecular Properties & Theory
74 ATOMIC AND MOLECULAR PHYSICS
CHROMIUM
COBALT
CONFIGURATION INTERACTION
COPPER
CORRECTIONS
CORRELATIONS
ELECTRON CORRELATION
ELECTRONIC STRUCTURE
ELEMENTS
IRON
MANGANESE
METALS
NICKEL
PERTURBATION THEORY
RADIATIVE CORRECTIONS
SCANDIUM
TITANIUM
TRANSITION ELEMENTS
VANADIUM