Self-consistent field configuration interaction

B. Mennucci, R. Cammi and J. Tomasi, Excited states and solvatochromic shifts within a nonequilibrium solvation approach A new formulation of the integral equation formalism method at the self-consistent field, configuration interaction, and multiconfiguration self-consistent field level, J. Chem. Phys., 109 (1998) 2798. 

R. Cammi and J. Tomasi, Nonequilibrium solvation theory for the polarizable continuum model - a new formulation at the SCF level with application to the case of the frequency-dependent linear electric-response function, Int. J. Quantum Chem., (1995) 465-74 B. Mennucci, R. Cammi and J. Tomasi, Excited states and solvatochromic shifts within a nonequilibrium solvation approach A new formulation of the integral equation formalism method at the self-consistent field, configuration interaction, and multiconfiguration self-consistent field level, J. Chem. Phys., 109 (1998) 2798-807 R. Cammi, L. Frediani, B. Mennucci, J. Tomasi, K. Ruud and K. V. Mikkelsen, A second-order, quadratically... 

For chemisorption of CH radicals, our model suggests to use Eq. (10b) for CH and CH2, but Eq. (10c) for CH3, projecting for all the species that preferred hollow site. In particular, for Ni(l 11) we obtained Qcmx - 116, 83, and 48 kcal/mol for x = 1,2, and 3, respectively (see later, Table VIII). For comparison, in the latest and most complete ab initio complete active space self-consistent field-configuration interaction (CASSCF-CI) cluster-type calculations of CH, on Ni(lll), Siegbahn et al. 74a,b) have found the hollow site to be universally preferred with Qcnx - 122, 85, and 49 kcal/mol for CH, CH2, and CH3, respectively. 

Of diatomic species, the best-studied molecule is CO, where ab initio cluster-type calculations of Qco are widely used (143). Still, one of the most accurate self-consistent field-configuration interaction (SCF-CI) allelectron calculations by Bagus et al. of the cluster Ni5-CO to mimic CO/Ni(100) gave Qco = 13 kcal/mol (143d), to be compared with the experimental value of 30 kcal/mol (and the BOC-MP estimate of 27 kcal/ mol). A much simpler and rather popular technique is the atom superposi-... 

Becke exchange and LYP correlation functional Complete Active Space Self-Consistent Field Configuration Interaction Complete Neglect Differential Overlap Density Functional Theory... 

Self consistent field, configuration interaction calculations (SCF, Cl) on 1,3,4-thiadiazoles indicate that the electronic state of the sulfur atom is described by s2pxpypz2 in which the two pz electrons are conjugated with the 7r-electron system of the rest of the molecule. The SCF eigenvalues and the molecular geometries are available (69JIC779). 

Predictions can be made about the suitability of different system trajectories on the basis of orbital symmetry conservation rules (207). The most suitable trajectory is an approximation to the reaction path of the reaction under study. The rules can also yield information about the possible structure of the activated complex. The correlation diagram technique has been improved in a series of books by Epiotis et al. (214-216). The method is based on self-consistent field-configuration interaction or valence bond (SCF-CI or VB) (including ionic structures) wave functions. Applications on reactions in the ground states as well as in the excited electronic states are impressive however, the price to be paid for the predictions seems to be rather high. 

Simons, J., Size extensivity correction for complete active space multiconfiguration self-consistent-field configuration interaction energies, J. Phys. Chem. 93, 626-627 (1989). 

The aim of this chapter is to review the current status of the quantum-mechanical calculation of electric and magnetic properties of isolated atoms and molecules. In view of the rapid advances made during the past decade in the calculation of ab initio molecular wavefunctions, we will clearly concentrate for the most part on the calculation of such properties using standard ab initio methods such as gaussian orbital LCAO-MO-SCF (linear combination of atomic orbital-miolecular orbital-self-consistent field), configuration interaction (Cl), coupled Hartree-Fock, and the like, but will also review similar calculations at the semi-empirical and empirical level where appropriate. For readers unfamiliar with the theory of electric and magnetic properties, the books by Davies and by Atkins review the subject thoroughly, whilst the more technical details of quantum-mechanical calculations on atoms and molecules have been described in many other places. ... 

The CD and UV spectra of the compound with a twisted n-electron system can be calculated by the jc-electron Self-Consistent-Field Configuration-Interaction Dipole-Velocity Molecular Orbital method (the Tc-electron SCF-CI-DV MO me-thod).8-10 In the dipole velocity method, the rotational strength I ba and dipole strength Dba which govern the sign and intensity of a CD Cotton effect and the intensity of a UV absorption band, respectively are formulated as follows ... 

T. J. Lee, W. D. Allen, and H. F. Schaefer, III, J. Chem. Phys., 87, 7063 (1987). The Analytic Evaluation of Energy First Derivatives for Two-Configuration Self-Consistent Field Configuration Interaction Wavefunctions. Applications to Ozone and Ethylene. 

A priori methods Self-consistent field Configuration interaction... 

It is well known that the PES cannot be given analytically in quantum chemistry, but can be calculated point by point through iterative solution of matrix eigenvalue problems arising from the application of LCAO-MO SCF Cl (Linear Combination of Atomic Orbitals - Molecular Orbital Self-Consistent-Field Configuration Interaction) methods. If... 

Since the establishment of necessary basis for accurate computation, simpler approaches with appropriate parameterization have been developed. In particular, parameterization of the PPP-SCF-CI (Pariser, Parr, Pople-self-consistent-field-configuration interaction) method has enabled /8-values (of sufficient accuracy to provide a basis for molecular design) to be obtained with much less powerful computers. Routines are now available for microcomputers that run in reasonable time with adequate accuracy [20]. 

A self-consistent field configuration interaction method in which simultaneous optimization of both the shapes of molecular orbitals and the contributions from different electronic configurations is carried out variational ly. 

Formulation of the Integral Equation Formalism Method at the Self-Consistent Field, Configuration Interaction, and Multiconfiguration Self-Consistent Field Level. 

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