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Ab initio effective core potentials (ECP’s) have been generated to replace the Coulomb, exchange, and core-orthogonality effects of the chemically inert core electron in the transition metal atoms Sc to Hg. For the sec...

Contracted Gaussian basis sets for molecular calculations are derived from uncontracted (12,8) and (12,9) sets for the neutral second row atoms, Z=11–18, and for the negative ions P−, S−, and Cl−. Calculations on...

The calculation of accurate electron affinities (EAs) of atomic or molecular species is one of the most challenging tasks in quantum chemistry. We describe a reliable procedure for calculating the electron affinity of an...

Various contracted Gaussian basis sets for atoms up to Kr are presented which have been determined by optimizing atomic self-consistent field ground state energies with respect to all basis set parameters, i.e., orbital ...

Contracted Gaussian basis sets of triple zeta valence (TZV) quality are presented for Li to Kr. The TZV bases are characterized by typically including a single contraction to describe inner shells and three basis functio...

In the past, basis sets for use in correlated molecular calculations have largely been taken from single configuration calculations. Recently, Almlöf, Taylor, and co-workers have found that basis sets of natural orbital...

Ab initio effective core potentials (ECP’s) have been generated to replace the innermost core electron for third-row (K–Au), fourth-row (Rb–Ag), and fifth-row (Cs–Au) atoms. The outermost core orbitals—correspo...

A consistent set of ab initio effective core potentials (ECP) has been generated for the main group elements from Na to Bi using the procedure originally developed by Kahn. The ECP’s are derived from all-electron numer...

Despite the remarkable thermochemical accuracy of Kohn–Sham density-functional theories with gradient corrections for exchange-correlation [see, for example, A. D. Becke, J. Chem. Phys. 96, 2155 (1992)], we believe tha...

An extended basis set of atomic functions expressed as fixed linear combinations of Gaussian functions is presented for hydrogen and the first-row atoms carbon to fluorine. In this set, described as 4–31 G, each inner ...

A contracted Gaussian basis set (6-311G**) is developed by optimizing exponents and coefficients at the Mo/ller–Plesset (MP) second-order level for the ground states of first-row atoms. This has a triple split in the v...

The 6-31G* and 6-31G** basis sets previously introduced for first-row atoms have been extended through the second-row of the periodic table. Equilibrium geometries for one-heavy-atom hydrides calculated for the two-basis...

The term ``sensitized luminescence'' in crystalline phosphors refers to the phenomenon whereby an impurity (activator, or emitter) is enabled to luminesce upon the absorption of light in a different type of center (sensi...

Magnetic and electric dipole transitions between levels of the 4fx configuration perturbed by a static crystalline field are treated. The expression obtained for the pure-electronic electric-dipole transition probability...

Previous attempts to combine Hartree–Fock theory with local density-functional theory have been unsuccessful in applications to molecular bonding. We derive a new coupling of these two theories that maintains their sim...

A method of ‘‘natural population analysis’’ has been developed to calculate atomic charges and orbital populations of molecular wave functions in general atomic orbital basis sets. The natural analysis is an alte...