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Hartree-Fock approximation multiconfiguration method

RPA, and CPHF. Time-dependent Hartree-Fock (TDHF) is the Hartree-Fock approximation for the time-dependent Schrodinger equation. CPHF stands for coupled perturbed Hartree-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]

Time-dependent Hartree-Fock (TDHF) approximation. See also Multiconfiguration time-dependent Hartree (MCTDH) method... [Pg.100]

Dynamical electron correlation effects are intrinsically included in DFT methods via the local and gradient-corrected correlation functionals. Most importantly, the nondynamlcal electron correlation effects have been partially accounted for via the exchange functionals (33,34). As a consequence, the multiconfiguration characters that often show up in traditional ab initio calculations using Hartree-Fock references could be sUghtly reduced in DFT methods. In other words, for approximating the true electronic stmctures of many-electron atoms and molecules... [Pg.349]

There are cases for which more than one solution is found, and it is possible that both may possess physical reality under certain conditions [12] (this will arise again in chapter 11). Furthermore, the Hartree-Fock method can be made multiconfigurational, i.e. several configurations can be mixed or superposed. An electron is then shared between different states, which goes beyond the independent particle approximation. The self-consistent method allows the mixing coefficients to be determined, but the configurations to be included must be specified at the outset, and there is no simple prescription as to which ones should be chosen or left out. [Pg.14]

In all the quantum chemical methods described in Chapters 10 to 12 the approximate electronic wavefunctions are built from molecular orbitals, which are the solutions of the Hartree-Fock equations Eq. (9.11) or their multiconfigurational extension. In all modern methods these molecular orbitals are expanded in a set of one-electron functions x ) called the basis set... [Pg.253]


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Approximate Hartree-Fock methods

Approximation methods

Approximation multiconfigurational

Hartree approximation

Hartree-Fock approximation

Hartree-Fock method

Hartree-Fock multiconfiguration

Multiconfiguration

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