Calculation of the electron affinities of the second row atoms: Al--Cl

Journal Article · Wed Sep 01 00:00:00 EDT 1993 · Journal of Chemical Physics; (United States)

DOI:https://doi.org/10.1063/1.466148· OSTI ID:6242989

Woon, D E; Dunning, Jr, T H ^[1]

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1. Molecular Science Research Center, Pacific Northwest Laboratory P.O. Box 999, Richland, Washington 99352 (United States)

The electron affinities (EAs) of aluminum through chlorine have been calculated with multireference single and double excitation configuration interaction calculations (MRSD-CI) with the augmented correlation consistent basis sets of Woon and Dunning [J. Chem. Phys. [bold 98], 1358 (1993)]. The orbital space for the complete active space (CAS) wave functions is systematically expanded beyond the Hartree--Fock wave function by inclusion of additional [ital s], [ital p], and [ital d] orbitals. This approach provides a well balanced treatment of the neutral and ionic charge states and led to accurate EAs for hydrogen and the first row atoms [R. A. Kendall, T. H. Dunning, Jr., and R. J. Harrison, J. Chem. Phys. [bold 96], 6796 (1992)]. The best MRSD-CI values for the EAs (in eV) of the second row atoms are Al, 0.440; Si, 1.413; P, 0.689; S, 2.023; and Cl, 3.606. Inclusion of spin--orbit effects in the calculated EAs yields (experimental values in parentheses): Al, 0.437 (0.441); Si, 1.395 (1.385); P, 0.700 (0.746); S, 2.019 (2.077); and Cl, 3.570 (3.613). The amenability of the correlation consistent basis sets for extrapolating to the complete basis set limit has also been exploited in this work. The neutral and anion energies are extrapolated separately in order to account for the different convergence rates in the energies of the two species. The extrapolated values of the EAs, including an empirical spin--orbit correction, are Al, 0.438; Si, 1.395; P, 0.713; S, 2.047; and Cl, 3.596. Additional calculations suggest that the remaining error is a measure of the residual imbalance in the MRSD-CI treatments of the neutral and anion. Extrapolated EAs for the first row atoms are also reported.

• DOE Contract Number: AC06-76RL01830; FG06-89ER75522
• OSTI ID: 6242989
• Journal Information: Journal of Chemical Physics; (United States), Vol. 99:5; ISSN 0021-9606
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
ALUMINIUM
AFFINITY
CHLORINE
PHOSPHORUS
SILICON
SULFUR
ANIONS
ATOMS
CONFIGURATION INTERACTION
ENERGY
ERRORS
EXCITATION
EXTRAPOLATION
HARTREE-FOCK METHOD
WAVE FUNCTIONS
CALCULATION METHODS
CHARGED PARTICLES
ELEMENTS
ENERGY-LEVEL TRANSITIONS
FUNCTIONS
HALOGENS
IONS
METALS
NONMETALS
NUMERICAL SOLUTION
SEMIMETALS
664100* - Theory of Electronic Structure of Atoms & Molecules- (1992-)