Molcas: a program package for computational chemistry.

Critic2: A program for real-space analysis of quantum chemical interactions in solids

Relativistic pseudopotentials: their development and scope of applications.

In this paper we formulate a model potential approach to take into account the crystalline environment within the Hartree–Fock–Roothaan formalism. The formulation is based on the assumption that the theory of separability of many‐electron systems may be applicable to the group of electrons within a reference cluster and the groups of electrons on a set of external lattice sites which, in turn, can be represented according to the ab initio model potential method. The characteristics of the model potentials permit to analyze the contributions to the cluster energies and wave functions of different environmental effects, such as point‐charge and charge‐density Coulomb interactions and quantum interactions (exchange and orthogonality). The formalism is applied to the SCF calculation on the ground state of the octahedaral CuCl5−6 cluster (all‐electron calculation) embedded in a NaCl lattice which is represented by 118 model‐potential ions and 604 point‐charge ions. The calculation reveals that (i) the quantum ...

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The ab initio model potential representation of the crystalline environment. Theoretical study of the local distortion on NaCl:Cu+

Theory of chemisorption and reactions on metal surfaces

Atomic and molecular systems are often intuitively separated into almost independent subsystems as, for example, the core and valence parts of an atom. Consequently, if this separation provides a good approximation, one can obtain the states of the system from the states of the subsystems which best represent the entire system. In the light of the work of McWeeny, in which one assumes strong orthogonality among subsystem wavefunctions, we determine an effective Hamiltonian for a given subsystem which should properly describe the states of that subsystem. Previous work is shown to have dealt with an improper effective Hamiltonian.

A. A. Cantu

Papers

Theory of Separability of Many‐Electron Systems