Many-body methods are one of the most powerful tools that may be brought to bear to solve the electronic structure problem. While both of the following theories provide a complete path to obtain any quantity, many-body ...

The nuclear-electronic orbital (NEO) method is a multicomponent approach that allows the quantum mechanical treatment of electrons and specified protons on the same quantum mechanical level. NEO does not make the ...

Anharmonic vibrational many-body methods are developed for and applied to small molecules and extended systems in a bound potential energy surface (PES). Diagrammatically size-consistent and basis-set-free vibrational ...

The embedded-fragment scheme known as the binary interaction method (BIM) was extended to enable ab initio second-order many-body perturbation (MP2) theory simulations of molecular liquids and solids with nonorthogonal ...

The concept of the chemical bond is essential to our understanding of molecular phenomena. G. N. Lewis laid the groundwork for our understanding of chemical bonds nearly a century ago in his classic 1916 paper in the Journal ...

Quantum mechanical effects play an important role in dynamics of condensed phases. It is also well known that the difficulty of solving the full Schrödinger equation grows exponentially with time. One approach to cope up ...

A textbook example of a pericyclic reaction is the electrocyclic ring opening of cyclobutene. The stereochemical outcome of this reaction can typically be predicted using the Woodward-Hoffmann rules, which are based on ...

The forward-backward semiclassical dynamics (FBSD) approximation provides a rigorous and practically useful methodology for simulating the dynamics of condensed phase systems that exhibit quantum mechanical effects. It is ...

Chemical dynamics are essentially quantum mechanical processes. A great variety of chemical processes such as electron transfer and energy relaxation occur in condensed phase, reactants and products embedding in a non-reactive ...

The properties of semiconductor materials depends on the type, concentration and spatial distribution of the point and extended defects it contains. For ceramic oxide semiconductor materials, the concentration and diffusion ...