Self-consistent reaction field methods

SCRF (self-consistent reaction field) method for including solvation effects in ah initio calculations... 

There is a fundamental difference between Eqs. 4.12 and 4.15 despite their apparent similarity. The term electron density (see Eq. 4.13), whereas the term Vcxt in Eq. 4.12, is constant in the SCF procedure. To reflect this fact, the approach based on Eqs. 4.13-4.15 is frequently called the Self-Consistent Reaction Field method (SCRF). (Throughout the text, AXY/SCRF denotes combined quantum-mechanical/reaction field calculations where XXX specifies the quantum-mechanical method.)... 

Multiconfigurational Self-Consistent Reaction Field Method. 

K. V. Mikkelsen, H. Agren, H. J. A. Jensen, and T. Helgaker, A Multiconfigurational self-consistent reaction-field method, J. Chem. Phys. 89, 3086-3095 (1988). 

The strength of the N H- -O bridge of ort/zo-amino-furanaldehyde, ealeu-lated as 26.02 kJ/mol at B3LYP/6-31+G level (with respect to the Z con-former) was found about 5 kJ/mol lower than that of the N H- -S hydrogen bond of ort/zo-amino-furanthioaldehyde (30.92 kJ/mol) [238]. Such values become 14.06 and 16.86 kJ/mol, respectively, when calculated in DMSO solution (a = 46.7) following the Onsager self-consistent reaction field method. 

The self-consistent reaction field method [19,48,49] can be used to calculate the electrostatic interaction energy, Ed, between the solute and its reaction field... 

Karelson et al. [124] had also carried out a comparative analysis of the molecular descriptors calculated for the isolated molecules (gas phase) and for the molecules embedded into a dielectric continuum corresponding to aqueous solution. The self-consistent reaction field method [125] was used for the latter calculations. The results indicated that, in general, the quantum-chemically derived descriptors are rather insensitive towards the change in the environment surrounding the molecule. However, the most influenced are the polarizability and several other MO-related descrip-... 

SCRF self-consistent reaction field (method)... 

A self-consistent reaction field method (SCRF) has been developed at the level of Hartree-Fock theory to solve the respective Schrodinger equation ... 

Despite the demands presented by such a calculation, a number of researchers have used ab initio models to treat the electronic and nuclear degrees of freedom for the quantum motif in molecular mechanics, energy minimization studies. Examples of this include the self-consistant reaction field methods developed by Tapia and coworkers [42-44], which represent only the quantum motif explicitly and use continuum models for the environmental effects (classical and boundary regions), and the methods implemented by Kollman and coworkers [45] in their studies of condensed phase (chemical and biochemical) reaction mechanisms. In both of these implementations the expectation value of the quantum motif Hamiltonian, defined in Eqs. (11) and (14) above, is treated at the Hartree Fock level with relatively small basis sets. 

Moreau Y, Loss P-F, Assfeld X (2004) Solvent effects on the asymmetric Diels Alder reaction between cyclopentadiene and ( )-menthyl acrylate revisited with the three-layer hybrid local self-consistent field/molecular mechanics/self-consistent reaction field method. Theor Chem Ace 112 228-239... 

Here M denotes the electronic part of the quantum mechanical operator associated with the m elements of multipole of rank / The methods based on the definition given by the equation (9) are referred as self-consistent reaction field methods (SCRF). 

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. 

Basis Sets Correlation Consistent Sets Configuration Interaction Coupled-cluster Theory Density Functional Applications Density Functional Theory Applications to Transition Metal Problems G2 Theory Integrals of Electron Repulsion Integrals Overlap Linear Scaling Methods for Electronic Structure Calculations Localized MO SCF Methods Mpller-Plesset Perturbation Theory Monte Carlo Quantum Methods for Electronic Structure Numerical Hartree-Fock Methods for Molecules Pseudospectral Methods in Ab Initio Quantum Chemistry Self-consistent Reaction Field Methods Symmetry in Hartree-Fock Theory. 

AMI COSMO and COSMO-RS Hydrogen Bonding 1 Hydrogen Bonding 2 Intermolecular Interactions by Perturbation Theory MNDO PM3 Self-consistent Reaction Field Methods Solvation Modeling Water Clusters,... 

It may be noted here that the theoretical developments below apply also to other solution chemistry problems of current interest. Electronic structure calculations for species in solution often append to the free energy a contribution to represent cavitation (see Self-consistent Reaction Field Methods Cavities). This is a free energy cost to open space for the solute in the solvent. Theories that solve that problem for water should be carried over to other solvents too. 

MP methods have been developed for both spin-restricted HF (RHF), spin-unrestricted HF (UHF), and restricted open-shell HF (ROHF) wavefunctions to investigate both closed- and open-shell systems (see Table 2). For the calculation of electron systems with multireference character such as biradicals various multireference state (MRS) MP methods have been developed (Table 2). All these methods describe atoms, molecules, and reaction systems in the gas phase. However, many chemical reactions take place in solution phases. For this purpose, MP methods are available that start from a solvent corrected wavefunction where mostly polarizable continuum models are used (see Self-consistent Reaction Field Methods). 

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