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Multiconfiguration

Once the requisite one- and two-electron integrals are available in the MO basis, the multiconfigurational wavefunction and energy calculation can begin. Each of these methods has its own approach to describing tlie configurations d),. j included m the calculation and how the C,.] amplitudes and the total energy E are to be... [Pg.2185]

Olsen J and J0rgensen P 1995 Time-dependent response theory with applications to self-consistent field and multiconfigurational self-consistent field wave functions Modern Electronic Structure Theory vo 2, ed D R Yarkony (Singapore World Scientific) pp 857-990... [Pg.2200]

Werner H-J 1987 Matrix-formulated direct multiconfigurational self-consistent field and multi reference configuration interaction methods Adv. Chem. Phys. 69 1... [Pg.2355]

Shepard R 1987 The multiconfiguration self-consistent field method [Pg.2360]

The time dependence of the molecular wave function is carried by the wave function parameters, which assume the role of dynamical variables [19,20]. Therefore the choice of parameterization of the wave functions for electronic and nuclear degrees of freedom becomes important. Parameter sets that exhibit continuity and nonredundancy are sought and in this connection the theory of generalized coherent states has proven useful [21]. Typical parameters include molecular orbital coefficients, expansion coefficients of a multiconfigurational wave function, and average nuclear positions and momenta. We write... [Pg.224]

Some details of END using a multiconfigurational electronic wave function with a complete active space (CASMC) have been introduced in terms of an orthonormal basis and for a fixed nuclear framework [25], and were recently [26] discussed in some detail for a nonoithogonal basis with electron translation factors. [Pg.233]

In order to make END better suited to the application of low energy events it is important to include an explicitly correlated description of the electron dynamics. Therefore multiconfigurational [25] augmentations of the minimal END are under development. [Pg.234]

If the PES are known, the time-dependent Schrbdinger equation, Eq. (1), can in principle be solved directly using what are termed wavepacket dynamics [15-18]. Here, a time-independent basis set expansion is used to represent the wavepacket and the Hamiltonian. The evolution is then carried by the expansion coefficients. While providing a complete description of the system dynamics, these methods are restricted to the study of typically 3-6 degrees of freedom. Even the highly efficient multiconfiguration time-dependent Hartree (MCTDH) method [19,20], which uses a time-dependent basis set expansion, can handle no more than 30 degrees of freedom. [Pg.252]

The multiconfigurational self-consistent field ( MCSCF) method in whiehthe expeetation value < T H T>/< T T>is treated variationally and simultaneously made stationary with respeet to variations in the Ci and Cy,i eoeffieients subjeet to the eonstraints that the spin-orbitals and the full N-eleetron waveflmetion remain normalized ... [Pg.483]

RPA, and CPHF. Time-dependent Hartree-Fock (TDFIF) is the Flartree-Fock approximation for the time-dependent Schrodinger equation. CPFIF stands for coupled perturbed Flartree-Fock. The random-phase approximation (RPA) is also an equivalent formulation. There have also been time-dependent MCSCF formulations using the time-dependent gauge invariant approach (TDGI) that is equivalent to multiconfiguration RPA. All of the time-dependent methods go to the static calculation results in the v = 0 limit. [Pg.259]

MCSCF (multiconfigurational self-consistent field) a correlated ah initio method... [Pg.365]

In this exercise, we will introduce the Complete Active Space Multiconfiguration SCF (CASSCF) method, using it to compute the excitation energy for the first excited state of acrolein (a singlet). The CIS job we ran in Exercise 9.3 predicted an excitation energy of 4.437 eV, which is rather for from the experimental value of 3.72 eV. We ll try to improve this prediction here. [Pg.228]

Multiconfiguration self-consistent field (MCSCF) theory aims to optimize simultaneously the LCAO coefficients and the Cl expansion coefficients in a wavefunction such as... [Pg.204]

The hetero-Diels-Alder reaction of aldehydes 12 with 2-azabutadienes 13 (Scheme 8.5) has been studied using high-level ab-initio multiconfigurational molecular orbital and density functionality calculation methods [28]. [Pg.318]

J. Olsen and P. Jorgensen. Time-Dependent Response Theory with Applications to Self-Consistent Field and Multiconfigurational Self-Consistent Field Wave Functions, in Modern Electronic Structure Theory, edited by D. R. Yarkony, volume 2, chapter 13, pp. 857-990. World Scientific, Singapore, 1995. [Pg.146]

The multiconfiguration extension of TDHF, or MCTDHF, can be developed also starting from Slater determinants... [Pg.330]

Approximations have been reviewed in the case of short deBroglie wavelengths for the nuclei to derive coupled quantal-semiclassical computational procedures, by choosing different types of many-electron wavefunctions. Time-dependent Hartree-Fock and time-dependent multiconfiguration Hartree-Fock formulations are possible, and lead to the Eik/TDHF and Eik/TDMCHF approximations, respectively. More generally, these can be considered special cases of an Eik/TDDM approach, in terms of a general density matrix for many-electron systems. [Pg.335]

Vilkas, M.J., Ishikawa, Y. and Koc, K. (1998) Quadratically convergent multiconfiguration Dirac-Fock and multireference relativistic configuration-interaction calculations for many-electron systems. Physical Review E, 58, 5096-5110. [Pg.224]


See other pages where Multiconfiguration is mentioned: [Pg.2175]    [Pg.2176]    [Pg.2187]    [Pg.2189]    [Pg.2332]    [Pg.465]    [Pg.14]    [Pg.174]    [Pg.133]    [Pg.491]    [Pg.491]    [Pg.194]    [Pg.203]    [Pg.48]    [Pg.56]    [Pg.112]    [Pg.320]    [Pg.330]    [Pg.34]    [Pg.65]    [Pg.44]    [Pg.219]    [Pg.381]   
See also in sourсe #XX -- [ Pg.19 ]




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A Multiconfigurational Study

Approximation multiconfigurational

Basis multiconfiguration

Bond length multiconfiguration self-consistent

Configuration functions multiconfigurational second-order

Configuration interaction multiconfigurational second-order

Correlation by Multiconfigurational SCF Methods

Coupled multiconfiguration Hartree Fock

Coupled-perturbed multiconfigurational

Derivatives multiconfiguration self-consistent field

Dirac-Fock multiconfiguration

Dirac—Fock calculations, multiconfiguration

Electron correlation multiconfiguration-based methods

Electronic energy multiconfiguration self-consistent field

Fermi-vacuum invariance in multiconfiguration

Fermi-vacuum invariance in multiconfiguration perturbation theory

Gradients multiconfiguration self-consistent field

Hartree-Fock approach multiconfiguration

Hartree-Fock approximation multiconfiguration method

Hartree-Fock multiconfiguration

Molecular orbitals multiconfigurational second-order

Multiconfiguration (MC) TDHF theory

Multiconfiguration Configuration Interaction

Multiconfiguration Dirac-Fock SCF

Multiconfiguration Dirac-Hartree-Fock

Multiconfiguration Dirac-Hartree-Fock MCDHF)

Multiconfiguration SCF (MCSCF)

Multiconfiguration SCF Theory

Multiconfiguration SCF calculations

Multiconfiguration SCF method

Multiconfiguration Self-Consistent-Field Wave Functions

Multiconfiguration VB

Multiconfiguration VB theory. Non-orthogonal orbitals

Multiconfiguration VB theory. Orthogonal orbitals

Multiconfiguration Valence Bond Methods with Optimized Orbitals

Multiconfiguration methods

Multiconfiguration molecular mechanics

Multiconfiguration quasi-degenerate

Multiconfiguration quasi-degenerate perturbation theory

Multiconfiguration random phase

Multiconfiguration random phase approximation

Multiconfiguration reference function

Multiconfiguration self-consistent

Multiconfiguration self-consistent field

Multiconfiguration self-consistent field Hartree-Fock

Multiconfiguration self-consistent field MC.SCF)

Multiconfiguration self-consistent field MCSCF)

Multiconfiguration self-consistent field MCSCF) method

Multiconfiguration self-consistent field calculations

Multiconfiguration self-consistent field dynamics

Multiconfiguration self-consistent field energy

Multiconfiguration self-consistent field implementation

Multiconfiguration self-consistent field response functions

Multiconfiguration self-consistent field systems

Multiconfiguration self-consistent field theory

Multiconfiguration self-consistent-field method

Multiconfiguration time-dependent

Multiconfiguration time-dependent Hartree

Multiconfiguration time-dependent Hartree MCTDH) method

Multiconfiguration time-dependent Hartree MCTDH) method, quantum

Multiconfiguration time-dependent Hartree dynamics

Multiconfiguration time-dependent Hartree method

Multiconfiguration time-dependent Hartree propagation

Multiconfiguration time-dependent theory

Multiconfiguration valence bond

Multiconfiguration wave function

Multiconfiguration wavefunction

Multiconfigurational

Multiconfigurational Hartree Fock response

Multiconfigurational Linear Response Functions

Multiconfigurational SCF

Multiconfigurational SCF method

Multiconfigurational SCF theory

Multiconfigurational Self-Consistent Field method (MC SCF)

Multiconfigurational approaches

Multiconfigurational calculations

Multiconfigurational density function theory

Multiconfigurational effect

Multiconfigurational energy

Multiconfigurational energy computational procedure

Multiconfigurational energy variational coefficients

Multiconfigurational linear response

Multiconfigurational linear response MCLR)

Multiconfigurational linear response wavefunction

Multiconfigurational methods

Multiconfigurational molecular mechanics

Multiconfigurational perturbation theory

Multiconfigurational polarization propagator

Multiconfigurational polarization propagator approximation

Multiconfigurational quantum methods

Multiconfigurational quasidegenerate

Multiconfigurational quasidegenerate perturbation theory

Multiconfigurational reference

Multiconfigurational second order

Multiconfigurational second-order applications

Multiconfigurational second-order compounds

Multiconfigurational second-order development

Multiconfigurational second-order limits

Multiconfigurational second-order perturbation theory

Multiconfigurational second-order structure

Multiconfigurational self consistent field MCSCF) method

Multiconfigurational self-consistent

Multiconfigurational self-consistent field

Multiconfigurational self-consistent field MCSCF)

Multiconfigurational self-consistent field MCSCF) model

Multiconfigurational self-consistent field MCSCF) technique

Multiconfigurational self-consistent field MCSCF) wave functions

Multiconfigurational self-consistent field calculations

Multiconfigurational self-consistent field method

Multiconfigurational self-consistent field orbitals

Multiconfigurational self-consistent field wave function

Multiconfigurational self-consistent field wavefunction

Multiconfigurational states

Multiconfigurational techniques

Multiconfigurational time-dependent

Multiconfigurational time-dependent Hartree

Multiconfigurational time-dependent Hartree (MCTDH) approach

Multiconfigurational time-dependent Hartree MCTDH)

Multiconfigurational time-dependent Hartree method

Multiconfigurational time-dependent Hartree-Fock

Multiconfigurational treatment

Multiconfigurational wave function

Multiconfigurational wave function electron correlation

Multiconfigurational wavefunctions

Open multiconfigurational study

Orbital-optimized multiconfiguration

Orbital-optimized multiconfiguration VB methods

Random-phase approximation multiconfigurational

Relativistic Multiconfiguration Self-Consistent Field Theory

SCF multiconfiguration

Self-consistent field, Hartree-Fock multiconfigurational

Spin multiconfigurational study

State-averaged multiconfiguration

State-averaged multiconfiguration self-consistent

The multiconfigurational self-consistent field model

Time-dependent multiconfigurational Hartree method applications

Wave operators, multiconfigurational

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