Chemisorption of oxygen and hydrogen atoms onto a 13 atom aluminum cluster is investigated theoretically. Oxygen atoms are found to remain on the outside of the cluster, and at low coverage, to expand the Al–Al bond length by 0.42 bohr. Hydrogen atoms penetrate into the cluster resulting in a... mehr

The structure and energetics of the alkali and alkaline-earth monohydroxides are studied at both the self-consistent-field and singles plus doubles configuration-interaction level using Gaussian basis sets of at least triple-zeta plus double polarization quality. BeOH is found to be bent, with a... mehr

Theoretical spectroscopic parameters are presented at the self-consistent-field and singles-plus-doubles configuration-interaction (SDCI) levels for the ground states of the positive ions of the alkaline-earth fluorides, oxides, and hydroxides. The alkaline-earth fluoride and hydroxide ions are... mehr

Ab initio calculations at the self-consistent-field (SCF), singles plus doubles configuration-interaction (SDCI), and coupled pair functional (CPF) level are reported for the dipole moments, μe, and dipole derivatives, (∂μ/∂r)re, of the X 2Σ+ ground states of BeF, BeCl, MgF, MgCl, CaF,... mehr

The electron affinity of oxygen is computed to be 1.287 eV, at the full CI level using a 6s5p3d2f Slater-type orbital basis and correlating only the 2p electrons. The best CASSCF–MRCI result including only 2p correlation is 1.263 eV. However, inclusion of 2s intrashell and 2s2p intershell... mehr

Spectroscopic parameters (De,re,μe) are determined for the second-row transition metal hydrides using large valence basis sets in conjunction with relativistic effective core potentials (RECPs). All-electron calculations are also performed for YH and AgH to calibrate the RECP results. Electron... mehr

The spectroscopic parameters and separations between the three low-lying X 3Πu, A 3Σ−g, and a 1Σ+g states of Al2 are studied as a function of both the one-particle and n-particle basis sets. Approximate correlation treatments are calibrated against full CI calculations correlating the six... mehr

Energy optimized, near Hartree–Fock quality Gaussian basis sets ranging in size from (17s12p) to (20s15p) are reported for the ground states of the second-row atoms and for Na (2P), Na+, Na−, Mg (3P), P−, S−, and Cl−. In addition, optimized supplementary functions are given for the... mehr

Large randomly sparse matrix vector products are important in a number of applications in computational chemistry, such as matrix diagonalization and the solution of simultaneous equations. Vectorization of this process is considered for the CRAY XMP, CRAY 2, and CYBER 205, using a matrix of... mehr

Copyright: Copyright © 1987 John Wiley & Sons, Inc. mehr

Ab initio calculations are used to determine accurate spectroscopic constants (re, ωe, De ) for the X 2Π and A 2Σ+ states of the alkali sulfides (LiS–RbS) and the X 1Σ+, a 3Π, and A 1Π states of the alkaline–earth sulfides (BeS–SrS). In contrast to the alkali oxides, all of the alkali... mehr