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Field methods

Onsager s original reaction field method imposes some serious lunitations the description of the solute as a point dipole located at the centre of a cavity, the spherical fonn of the cavity and the assumption that cavity size and solute dipole moment are independent of the solvent dielectric constant. [Pg.837]

Kirkwood generalized the Onsager reaction field method to arbitrary charge distributions and, for a spherical cavity, obtained the Gibbs free energy of solvation in tenns of a miiltipole expansion of the electrostatic field generated by the charge distribution [12, 1 3]... [Pg.837]

Shepard R 1987 The multieonfiguration self-eonsistent field method Advances in Chemical Physics vol LXIX, ed K P Lawley (New York Wiley-Interseienee) pp 63-200... [Pg.2196]

Wahl A C and Das G 1977 The multieonfiguration self-eonsistent field method Modem Theoretical Chemistry vo 3, ed H F III Sehaefer (New York Plenum) pp 51-78 eovers the earlier history on this topie... [Pg.2196]

Roos B O 1987 The complete active space self-consistent field method and its applications in electronic structure calculations Adv. Chem. Phys. 69 399-445... [Pg.2200]

In the reaction field method, the space surrounding a dipolar molecule is divided into two regions (i) a cavity, within which electrostatic interactions are sunnned explicitly, and (ii) a surrounding medium, which is assumed to act like a smooth continuum, and is assigned a dielectric constant e. Ideally, this quantity will be... [Pg.2255]

When carried out properly, the results of the reaction field method and the Ewald sum are consistent [67]. Recently, the reaction field method has been reconnnended on grounds of elTiciency and ease of progrannning [68, 69]. The... [Pg.2255]

The mean field teclmique is one of the most robust and simple methods used to handle larger molecules in gas and liquid enviromnents [M, 134. 135 and 136]. The basic premise of all mean-field methods is that the fiill wavefiinction represents N very weakly coupled modes (2 ) and can be approximated as... [Pg.2312]

The fimdamental disadvantage of the mean-field method is that it does not allow modes to respond in a correlated maimer to each other. This problem can be somewhat alleviated by a good definition of the relevant coordinate system [134. 136]. (An extension of mean-field methods that does allow for coupling [137. 138 and 139] will be discussed later.)... [Pg.2312]

Gerber, R. B., Ratner, M. A. Self-consistent field methods for vibrational excitations in polyatomic systems. Adv. Chem. Phys. 70 (1988) 97-132... [Pg.394]

A descriptor for the 3D arrangement of atoms in a molceulc can be derived in a similar manner. The Cartesian coordinates of the atoms in a molecule can be calculated by semi-empirical quantum mechanical or molecular mechanics (force field) methods, For larger data sets, fast 3D structure generators are available that combine data- and rule-driven methods to calculate Cartesian coordinates from the connection table of a molecule (e.g., CORINA [10]). [Pg.517]

The range of systems that have been studied by force field methods is extremely varied. Some force fields liave been developed to study just one atomic or molecular sp>ecies under a wider range of conditions. For example, the chlorine model of Rodger, Stone and TUdesley [Rodger et al 1988] can be used to study the solid, liquid and gaseous phases. This is an anisotropic site model, in which the interaction between a pair of sites on two molecules dep>ends not only upon the separation between the sites (as in an isotropic model such as the Lennard-Jones model) but also upon the orientation of the site-site vector with resp>ect to the bond vectors of the two molecules. The model includes an electrostatic component which contciins dipwle-dipole, dipole-quadrupole and quadrupole-quadrupole terms, and the van der Waals contribution is modelled using a Buckingham-like function. [Pg.249]

In the reaction field method, a sphere is constructed around the molecule with a radius equal to the cutoff distance. The interaction with molecules that are within the sphere is calculated explicitly. To this is added the energy of interaction with the medium beyond the sphere, which is rnodelled as a homogeneous medium of dielectric constant g (Figure 6.23). The electrostatic field due to the surrounding dielectric is given by ... [Pg.353]

The reaction field method. The shaded arrow represents the mm of the dipoles of the other molecules within sphere. [Pg.354]

We have said that the Schroedinger equation for molecules cannot be solved exactly. This is because the exact equation is usually not separable into uncoupled equations involving only one space variable. One strategy for circumventing the problem is to make assumptions that pemiit us to write approximate forms of the Schroedinger equation for molecules that are separable. There is then a choice as to how to solve the separated equations. The Huckel method is one possibility. The self-consistent field method (Chapter 8) is another. [Pg.172]

Semiempirical methods, of whieh there are quite a few, differ in the proportion of caleulations from first prineiples and the relianee on empirieal substitutions. Different methods of parameterization also lead to different semiempirieal methods. Huekel and extended Huekel ealeulations are among the simplest of the semiempirieal methods. In the next two seetions, we shall treat a semiempirieal method, the self eonsistent field method, developed by Paiiser and Parr (1953) and by Pople (1953), whieh usually goes under the name of the PPP method. [Pg.248]

Application of the variational self-consistent field method to the Haitiee-Fock equations with a linear combination of atomic orbitals leads to the Roothaan-Hall equation set published contemporaneously and independently by Roothaan and Hall in 1951. For a minimal basis set, there are as many matr ix elements as there are atoms, but there may be many more elements if the basis set is not minimal. [Pg.278]

II. Ab Initio, Semi-Empirical and Empirical Force Field Methods... [Pg.519]

SCRF (self-consistent reaction field) method for including solvation effects in ah initio calculations... [Pg.368]

Chem comes with default parameter sets, Amber2 and Amber3 in the case of the AMBER method. It is possible, however, to define an arbitrary number of additional parameter sets for the AMBER method (or for any of the other three force field methods). These user-defined parameter sets can be specified in the Parameters dialog box and integrated into HyperChem, in the same way as the default sets. [Pg.197]


See other pages where Field methods is mentioned: [Pg.163]    [Pg.838]    [Pg.1662]    [Pg.2175]    [Pg.2255]    [Pg.2311]    [Pg.2312]    [Pg.2342]    [Pg.2344]    [Pg.10]    [Pg.373]    [Pg.440]    [Pg.338]    [Pg.197]    [Pg.224]    [Pg.46]    [Pg.130]    [Pg.133]    [Pg.183]    [Pg.252]    [Pg.348]    [Pg.413]    [Pg.520]    [Pg.224]    [Pg.226]    [Pg.230]    [Pg.163]   
See also in sourсe #XX -- [ Pg.45 , Pg.128 , Pg.128 , Pg.129 ]




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A simple finite difference method for plane, steady-state temperature fields

Advantages and Limitations of Force Field Methods

Analytical method field test results

Anti conformations, force field methods

Approximate Methods Hybrid Force Fields

Approximate methods of field calculation in induction logging

Assays, tests, assessment methods field studies

Atomistic methods force field

Atoms self-consistent field method

Bending energies, force field methods

Bond breaking self-consistent field methods

Bond dissociation force field methods

Cavities self-consistent reaction field methods

Clearing field methods

Comparative Molecular Field Analysis method

Comparison of the Near-Field Spectroscopic Methods

Complete Active Space Self-Consistent Field CASSCF) method

Complete active space self consistent field method

Computational Methods and Software for Bioelectric Field Problems hristopher R. Johnson

Computational methods empirical force fields

Continuous molecular fields methods

Coordination compounds force field methods

Coupled-perturbed self-consistent field methods

Cross terms force field methods

Crystal field method

Crystal field method effective Hamiltonian

Crystal force field methods

Crystal-field independent methods

Dark field methods

Density-based Hartree-Fock theory self-consistent field method

Dipole polarizability finite-field methods

Electric field jump methods

Electric field methods

Electric field methods applications

Electrical field jump method

Electrical field method

Electronic states self-consistent field method

Electronic structure methods self-consistent field theory

Electronic structure self-consistent field methods

Electrostatic energies force field methods

Empirical Force Field method

Empirical Force Field or Molecular Mechanics Methods

Excited states field method

Experimental methods inhomogeneous electric fields

Field Gradient Methods

Field Methods in Regional Geochemical Surveys

Field Signature Method

Field Signature Method (Electric Fingerprint)

Field Work and Laboratory Methods

Field analytical methods

Field assessment method

Field compensation method

Field desorption methods

Field diagnostic methods

Field emission fluctuation method

Field gradient spin methods

Field ionization method

Field measuring methods

Field method, oscillatory

Field methods soil water

Field optimized initial state method

Field screening methods

Field studies chemical methods

Field trials method

Field-Enhanced Fluorescence Quenching Methods

Field-based methods

Fields and sets of chains analytical method

Finite Volume Method for Calculation of Flow Field

Finite-field method

Finite-field method polarizability calculations

Force field method, prediction

Force field methods accuracy/generality

Force field methods advantages

Force field methods atom types

Force field methods computational considerations

Force field methods conjugated systems

Force field methods energy comparisons

Force field methods energy types

Force field methods errors

Force field methods functional forms

Force field methods functional groups

Force field methods generic parameters

Force field methods hydrogen bonds

Force field methods hyperconjugation

Force field methods limitations

Force field methods parameterization

Force field methods practical considerations

Force field methods reactive energy surfaces

Force field methods stretch energies

Force field methods structurally different molecules

Force field methods torsional energies

Force field methods transition structure modelling

Force field methods, molecular modeling

Force field-based methods

Force-field methods

Force-field methods, calculation

Force-field methods, calculation of molecular structure and energy

Four-field method

Fringe-field method

Galerkin method for electromagnetic field discretization

Generalized reaction field method

Ground state self-consistent field method

Hartree self-consistent-field method

Hartree-Fock theory force field methods

Hartrees Self-Consistent Field (SCF) Method

Hemmes ELECTRIC FIELD METHODS

High-field free-powder method

Hybrid force field electronic structure method

Hyperpolarizabilities finite-field method

Interaction Field Modified Hamiltonian method

Introduction the local field method

Kohn-Sham self-consistent-field methods

Ligand field theory method

Local consistent field method

Local field method

Local reaction field method

Local self-consistent field method

Magnetic Force in Nonuniform Fields Phase Analysis Method

Magnetic field perturbation method

Mean field methods

Mean reaction field method

Mean-field spin-orbit method

Mean-field trajectory method

Mean-field trajectory method classical-path approximation

Mean-field trajectory method discussion

Mean-field trajectory method nonadiabatic quantum dynamics

Mean-field trajectory method results

Method of orthogonal effective fields

Method using pulsed field gradient

Method, 320 Force field energy

Methods for Field-, Pilot-, and Bench-Scale Studies

Methods in Surface Kinetics Flash Desorption, Field Emission Microscopy, and Ultrahigh Vacuum Techniques Gert Ehrlich

Mixed quantum-classical methods mean-field trajectory

Molecular interaction field -based method

Molecular mechanics force field correlated methods

Molecular potential self-consistent-field method

Molecular self-consistent field methods

Molecular structure and energy, calculation of, by force-field methods

Morse potentials force field methods

Multi-Configuration Self Consistent Field MCSCF) methods

Multi-Configuration Self Consistent Field MRCI) methods

Multi-configuration self-consistent field electron correlation methods

Multi-configuration self-consistent field method

Multi-configurational self-consistent field MCSCF) method

Multi-frequency high-field methods

Multiconfiguration self-consistent field MCSCF) method

Multiconfiguration self-consistent-field method

Multiconfigurational Self-Consistent Field method (MC SCF)

Multiconfigurational self consistent field MCSCF) method

Multiconfigurational self-consistent field method

Mutually consistent field method

Nanoparticle field flow fractionation method

Near field methods

Near-field spectroscopic method

Neighbour list, in force field methods

Null-Field Method

Null-field method with distributed

Numerical Simulation and the Phase-Field Method

Other Methods to Estimate Crystal Field Parameters

Particle size measurement field scanning methods

Phase-field method

Polarizabilities finite-field methods

Post-self-consistent field methods

Potential energy surfaces force field methods

Pulse field gradient -NMR methods

Pulse field gradient method

Pulsed electric field method

Pulsed field-gradient NMR methods

Quantum Consistent force field method

Quantum mechanics self-consistent field methods

Quantum-mechanical charge field method

Random fields method

Rapid field method

Rapid field method residue levels

Reaction field methods

Reaction probability electric field methods

Reactive force field molecular simulation methods

Reactive force-field quantum chemical methods

Related Methods Pulsed Field Gradient NMR and Dynamic Light Scattering

Restricted Active Space Self-Consistent Field RASSCF) method

Restricted active space self-consistent field method

Results of the Self-consistent Field Method

Scaled quantum mechanical force field method

Schrodinger equation force field methods

Self-consistent Field plus Dispersion Method

Self-consistent field , evaluation methods

Self-consistent field Hartree-Fock method

Self-consistent field method

Self-consistent field method Hartree equations

Self-consistent field method Hartree-Fock equations

Self-consistent field method Slater determinant orbital function

Self-consistent field method averaging procedure

Self-consistent field method complete active space, combination with

Self-consistent field method computational chemistry

Self-consistent field method coordinate optimization

Self-consistent field method correction

Self-consistent field method correlation interactions

Self-consistent field method density functional theory hybrid

Self-consistent field method description

Self-consistent field method generalization

Self-consistent field method iterative minimization

Self-consistent field method limitation

Self-consistent field method minimization procedure

Self-consistent field method optimization

Self-consistent field method overview

Self-consistent field method quantization

Self-consistent field method quantum mechanical

Self-consistent field method reaction model, charge distribution

Self-consistent field method semiclassical

Self-consistent field method separability

Self-consistent field method total energy

Self-consistent field methods (SCF

Self-consistent field methods, correlation

Self-consistent field methods, correlation coefficients

Self-consistent field methods, effective

Self-consistent field methods, effective nuclear charge calculated using

Self-consistent field orbital approximation method Generating

Self-consistent field theory electron correlation methods

Self-consistent mean field methods

Self-consistent reaction field method

Self-consistent reaction field method, organic

Self-consistent-field method advantages

Self-consistent-field method brush

Self-consistent-field method case studies

Self-consistent-field method computation time compared with

Self-consistent-field method interactions

Self-consistent-field method lengths

Self-consistent-field method simulation

Selfconsistent field method

Semiempirical Selfconsistent Field Methods

Single-Configuration Self-Consistent Field Methods

Small-field methods

Spheres, field-fabricated fabrication methods

Spin-restricted Hartree-Fock method Self-consistent field

Spin-unrestricted Hartree-Fock method Self-consistent field

Taylor expansions force field methods

The Finite-Field Method

The Force-Field Method

The Hartree-Fock Self-consistent Field Method

The Mutually Consistent Field (MCF) Method

The Use of Self-consistent Field Methods to Obtain Atomic Orbitals

The magnetic field perturbation method (MFP)

The method of auxiliary fields

The self-consistent field method

Time-dependent self-consistent-field methods

Valence Bond Self-Consistent Field Method with Localized Orbitals

Valence complete active space self-consistent field methods

Variable electronegativity self-consistent field method

Variation method applied to hydrogen atom in electric field

Vibrational force field methods

Virtual Force Field method

Worker exposure field methods

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