λ-Density Functional Valence Bond: A Valence Bond-Based Multiconfigurational Density Functional Theory With a Single Variable Hybrid Parameter

A multiconfigurational hybrid density-functional theory.

We propose a multiconfigurational hybrid density-functional theory which rigorously combines a multiconfiguration self-consistent-field calculation with a density-functional approximation based on a linear decomposition of the electron-electron interaction. This gives a straightforward extension of the usual hybrid approximations by essentially adding a fraction λ of exact static correlation in...

Complementary evaluation of structure stability of perovskite oxides using bond-valence and density-functional-theory calculations

Estimation of structure stability is an essential issue in materials design and synthesis. Global instability index (GII) based on bond-valence method is applied as a simple indication, while density functional theory calculation is adopted for accurate evaluation of formation energy. We compare the GII and total energy of typical ABO3-type perovskite oxides and rationalize their relationship, ...

A chemist's guide to valence bond theory

Gas-phase valence-electron photoemission spectroscopy using density functional theory.

We present a tutorial overview of the simulation of gas-phase valence-electron photoemission spectra using density functional theory (DFT), emphasizing both fundamental considerations and practical applications, and making appropriate links between the two. We explain how an elementary quantum mechanics view of photoemission couples naturally to a many-body perturbation theory view. We discuss ...

Essay Valence Bond Theory for Chemical Dynamics

This essay provides a perspective on several issues in valence bond theory: the physical significance of semilocal bonding orbitals, the capability of valence bond concepts to explain systems with multireferences character, the use of valence bond theory to provide analytical representations of potential energy surfaces for chemical dynamics by the method of semiempirical valence bond potential...