Self-consistent field solvation model

Diastereoselectivity of the reactions of the cation 26 and the anion 29 derived from 25 (R2 = Me) was modeled by self-consistent reaction field solvation models obtained from ab initio SCF-MO calculations. The experimentally found cis/trans ratios confirmed the model (Scheme 1) <2002JOC2013>. 

S n2 displacements of Cl ion from MeCl, EtCl, and CICH2CH2CI by AcO- and by HO have been studied in ab initio molecular orbital calculations at the HF/6-31+G(d), MP2/6-31+G(d), and MP4/6-31+G(d) levels.92 The gas-phase reactions of HO have no overall barrier, but there is a small overall barrier for the reactions with AcO. A self-consistent reaction-field solvation model was used to examine the 5n2 reactions between MeCl and HO and between CICH2CH2CI and AcO- in solution. A... 

C. Amovilli and B. Mennucci, Self-consistent-field calculation of Pauli repulsion and dispersion contributions to the solvation free energy in the polarizable continuum model, J. Phys. Chem. B, 101 (1997) 1051. 

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... 

R. Cammi, B. Mennucci, K. Ruud, L. Frediani, K.V. Mikkelsen, J. Tomasi, A second order, quadratically convergent multiconfigurational self-consistent field polarizable continuum model for equilibrium and nonequilibrium solvation. J. Chem. Phys. 117, 13 (2002)... 

In a later stndy, a model for absolnte free energy of solvation of organic, small inorganic, and biological molecnles in aqneons media was described. From the Monte Carlo simnlation stndies of aqneons solvation and the hydrophobic effect, we assnme that some 250 or more solvent molecnles are involved in the process. To resolve this problem, the so-called self-consistent field (SCF) solvation model for the hydrophobic effect was described. ... 

A many-body perturbation theory (MBPT) approach has been combined with the polarizable continuum model (PCM) of the electrostatic solvation. The first approximation called by authors the perturbation theory at energy level (PTE) consists of the solution of the PCM problem at the Hartree-Fock level to find the solvent reaction potential and the wavefunction for the calculation of the MBPT correction to the energy. In the second approximation, called the perturbation theory at the density matrix level only (PTD), the calculation of the reaction potential and electrostatic free energy is based on the MBPT corrected wavefunction for the isolated molecule. At the next approximation (perturbation theory at the energy and density matrix level, PTED), both the energy and the wave function are solvent reaction field and MBPT corrected. The self-consistent reaction field model has been also applied within the complete active space self-consistent field (CAS SCF) theory and the eomplete aetive space second-order perturbation theory. ... 

Ten-no, S., Hirata, F., 8c Kato, S. (1994). Reference interaction site model self-consistent field study for solvation effect on carbonyl compounds in aqueous solution. Journal of Chemical Physics, 100,7443. 

Combined Quantum Mechanical and Molecular Mechanical Potentials Combined Quantum Mechanics and Molecular Mechanics Approaches to Chemical and Biochemical Reactivity Continuum Solvation Density Functional Theory (DFT), Hartree-Fock (HF), and the Self-consistent Field MNDO Monte Carlo Simulations for Liquids Quantum Mechanical/Molecular Mechanical (QM/MM) Coupled Potentials Quantum Mechanics/Molecular Mechanics (QM/MM) Self-consistent Reaction Field Methods Self-consistent Reaction Field Methods Cavities Solvation Modeling TURBOMOLE. 

N. Gresh, G. Tiraboschi, and D. R. Salahub, Biopolymers, 45(6), 405-425 (1998). Conformational Properties of a Model Alanyl Dipeptide and of Alanine-Derived Ohgopeptides Effects of Solvation in Water and in Organic Solvents - A Combined SIBFA/Continuum Reaction Field, ab Initio Self-Consistent Field, and Density Functional Theory Investigation. 

Solvation behavior can be effectively predicted using electronic structure methods coupled with solvation methods, for example, the combination of continuum solvation methods such as COSMO with DFT as implemented in DMoF of Accelrys Materials Studio. An attractive alternative is statistical-mechanical 3D-RISM-KH molecular theory of solvation that predicts, from the first principles, the solvation structure and thermodynamics of solvated macromolecules with full molecular detail at the level of molecular simulation. In particular, this is illustrated here on the adsorption of bitumen fragments on zeolite nanoparticles. Furthermore, we have shown that the self-consistent field combinations of the KS-DFT and the OFE method with 3D-RISM-KH can predict electronic and solvation structure, and properties of various macromolecules in solution in a wide range of solvent composition and thermodynamic conditions. This includes the electronic structure, geometry optimization, reaction modeling with transition states, spectroscopic properties, adsorption strength and arrangement, supramolecular self-assembly,"and other effects for macromolecular systems in pure solvents, solvent mixtures, electrolyte solutions, " ionic liquids, and simple and complex solvents confined in nanoporous materials. Currently, the self-consistent field KS-DFT/3D-RISM-KH multiscale method is available only in the ADF software. 

The Self-Consistent Reaction Field (SCRF) model considers the solvent as a uniform polarizable medium with a dielectric constant of s, with the solute M placed in a suitable shaped hole in the medium. Creation of a cavity in the medium costs energy, i.e. this is a destabilization, while dispersion interactions between the solvent and solute add a stabilization (this is roughly the van der Waals energy between solvent and solute). The electric charge distribution of M will furthermore polarize the medium (induce charge moments), which in turn acts back on the molecule, thereby producing an electrostatic stabilization. The solvation (free) energy may thus be written as... 

Marten, B., K. Kim, C. Cortis, R. A. Friesner, R. B. Murphy, M. N. Ringnalda, D. Sitkoff, and B. Honig. 1996. New Model for Calculation of Solvation Free Energies Correction to Self-consistent Reaction Field Continuum Dielectric Theory for Short-Range Hydrogen-Bonding Effects. J. Phys. Chem. 100, 11775. 

Hall, R. J., M. M. Davidson, N. A. Burton, and I. H. Hiller. 1995. Combined Density Functional Self-Consistent Reaction Field Model of Solvation. J. Phys. Chem. 99, 921. 

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