Rodney J. Bartlett

A full coupled-cluster singles and doubles model: The inclusion of disconnected triples

The coupled-cluster singles and doubles model (CCSD) is derived algebraically, presenting the full set of equations for a general reference function explicitly in spin–orbital f...

Many-Body Perturbation Theory and Coupled Cluster Theory for Electron Correlation in Molecules

Ten years ago in the Annual Review of Physical Chemistry. there was a review article entitled Many-Body Theories of the Electronic Structure of Atoms and Molecules, by Karl Free...

Many‐body perturbation theory, coupled‐pair many‐electron theory, and the importance of quadruple excitations for the correlation problem

Abstract Many‐body (diagrammatic) perturbation theory ( MBPT ), coupled‐pair many‐electron theory ( CPMET ), and configuration interaction ( CI ) are investigated with particula...

The full CCSDT model for molecular electronic structure

The full coupled-cluster model (CCSDT) single, double, and triple excitation method defined by the wave function exp(T1+T2+T3)‖Φ0〉 is formulated and computationally implemented ...

Towards a full CCSDT model for electron correlation

Coupled cluster models for electron correlation which include the effects of single, double, and triple excitation operators are analyzed. An alternate version of the approximat...

A coupled cluster approach with triple excitations

The coupled-cluster model for electron correlation is generalized to include the effects of connected triple excitation contributions. The detailed equations for triple excitati...

A systematic comparison of molecular properties obtained using Hartree–Fock, a hybrid Hartree–Fock density-functional-theory, and coupled-cluster methods

We present results of a systematic study of the theoretical determination of equilibrium geometries, harmonic frequencies, total atomization energies, and dipole moments using H...

Molecular Applications of Coupled Cluster and Many-Body Perturbation Methods

A series of molecular applications of many-body perturbation theory (MBPT) and the coupled-cluster doubles (CCD) model are described. Even though these methods have been availab...

The reduced linear equation method in coupled cluster theory.

A numerical procedure for efficiently solving large systems of linear equations is presented. The approach, termed the reduced linear equation (RLE) method, is illustrated by so...

Pair-correlation energies in sodium hydride with many-body perturbation theory

Many-body perturbation theory (MBPT) is applied to the electronic structure of the sodium hydride molecule using a basis set of Slater-type orbitals. Both a ${V}^{N}$ and a ${V}...

ELECTRON CORRELATION IN LARGE MOLECULES WITH MANY‐BODY METHODS

Towards a full CCSDT model for electron correlation. CCSDT-n models

Fifth-Order Many-Body Perturbation Theory and Its Relationship to Various Coupled-Cluster Approaches

Comparison of high-order many-body perturbation theory and configuration interaction for H2O

Highly correlated single-reference studies of the O3 potential surface. I. Effects of high order excitations on the equilibrium structure and harmonic force field of ozone

The potential energy surface of ozone in the vicinity of the equilibrium geometry is investigated by single-reference many-body perturbation theory (MBPT) and coupled-cluster (C...

The potential energy curve for the <i>X</i>1Σ<i>g</i>+ state of Mg2 calculated with many-body perturbation theory

The ground state potential curve for the van der waals molecule, Mg2, is calculated by adding to the Hartree–Fock potential curve those many-body perturbation theory (MBPT) corr...