Electronic structure methods

Multi-configurational self-consistent field

Multi-configurational self-consistent field (MCSCF) is a method in quantum chemistry used to generate qualitatively correct reference states of molecules in cases where Hartree–Fock and density functional theory are not adequate (e.g., for molecular ground states which are quasi-degenerate with low-lying excited states or in bond-breaking situations). It uses a linear combination of configuration state functions (CSF), or configuration determinants, to approximate the exact electronic wavefunction of an atom or molecule. In an MCSCF calculation, the set of coefficients of both the CSFs or determinants and the basis functions in the molecular orbitals are varied to obtain the total electronic wavefunction with the lowest possible energy. This method can be considered a combination between configuration interaction (where the molecular orbitals are not varied but the expansion of the wave function) and Hartree–Fock (where there is only one determinant, but the molecular orbitals are varied). MCSCF wave functions are often used as reference states for multireference configuration interaction (MRCI) or multi-reference perturbation theories like complete active space perturbation theory (CASPT2). These methods can deal with extremely complex chemical situations and, if computing power permits, may be used to reliably calculate molecular ground and excited states if all other methods fail. (Wikipedia).

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From playlist Multivariable Calculus

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From playlist Multivariable Calculus

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From playlist Multivariable Spaces and Functions

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In this video, I show a very neat result about dual spaces: Namely, any basis of V* is automatically a dual basis of some basis of V. Even though this result is very interesting, it's the proof that makes this very exciting, by simply using the fact that V and V** are 'very' isomorphic. En

From playlist Dual Spaces

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From playlist Dual Spaces

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From playlist Worldwide Multivariable Calculus

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Dual basis definition and proof that it's a basis In this video, given a basis beta of a vector space V, I define the dual basis beta* of V*, and show that it's indeed a basis. We'll see many more applications of this concept later on, but this video already shows that it's straightforwar

From playlist Dual Spaces

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From playlist Multivariable Calculus

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From playlist Workshop: Mathematical and Numerical Aspects of Gravitation

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Lecture 07-Jack Simons Electronic Structure Theory- Configuration interaction theory

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From playlist U of Utah: Jack Simons' Electronic Structure Theory course

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From playlist Summer of Math Exposition Youtube Videos

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Laura Gagliardi - Localized-Wave-Function in Quantum Chemistry and Extension to Quantum Computers

Recorded 30 March 2022. Laura Gagliardi of the University of Chicago presents "Localized-Wave-Function Methods in Quantum Chemistry and Their Extension to Quantum Computers" at IPAM's Multiscale Approaches in Quantum Mechanics Workshop. Abstract: Quantum chemistry calculations of large, st

From playlist 2022 Multiscale Approaches in Quantum Mechanics Workshop

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From playlist PowerShell + DevOps Global Summit 2018

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From playlist Quantum Fields, Geometry and Representation Theory

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From playlist PowerShell + DevOps Global Summit 2018

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From playlist U of Utah: Jack Simons' Electronic Structure Theory course

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(PP 6.2) Multivariate Gaussian - examples and independence

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From playlist Probability Theory

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M Ferrero - Analytical approximate Solvers

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From playlist Strongly correlated systems: From models to materials

Related pages

Douglas Hartree | Complete active space perturbation theory | Density functional theory | Configuration interaction | Hartree–Fock method