Physical Review Letters, ISSN 0031-9007, 2006, Volume 97, Issue 14, p. 143002

Two-electron reduced density matrices (2-RDMs) of many-electron molecules are directly determined without calculation of their wave functions by solving the...

SYSTEMS | WAVE-FUNCTIONS | IRREDUCIBLE BRILLOUIN CONDITIONS | PHYSICS, MULTIDISCIPLINARY

SYSTEMS | WAVE-FUNCTIONS | IRREDUCIBLE BRILLOUIN CONDITIONS | PHYSICS, MULTIDISCIPLINARY

Journal Article

Journal of Chemical Theory and Computation, ISSN 1549-9618, 05/2016, Volume 12, Issue 5, pp. 2260 - 2271

A large-scale implementation of the complete active space self-consistent field (CASSCF) method is presented. The active space is described using the...

RENORMALIZATION-GROUP | MOLECULAR CALCULATIONS | IRREDUCIBLE BRILLOUIN CONDITIONS | GROUND-STATE | REPRESENTABILITY CONDITIONS | PHYSICS, ATOMIC, MOLECULAR & CHEMICAL | CORRELATED CALCULATIONS | CHEMISTRY, PHYSICAL | ELECTRONIC-STRUCTURE CALCULATIONS | CONTRACTED SCHRODINGER-EQUATIONS | 2-DIMENSIONAL GRAPHENE NANORIBBONS | SEMIDEFINITE PROGRAMS | Energy gap | Orbitals | Approximation | Computation | Mathematical analysis | Density | Standards | Optimization

RENORMALIZATION-GROUP | MOLECULAR CALCULATIONS | IRREDUCIBLE BRILLOUIN CONDITIONS | GROUND-STATE | REPRESENTABILITY CONDITIONS | PHYSICS, ATOMIC, MOLECULAR & CHEMICAL | CORRELATED CALCULATIONS | CHEMISTRY, PHYSICAL | ELECTRONIC-STRUCTURE CALCULATIONS | CONTRACTED SCHRODINGER-EQUATIONS | 2-DIMENSIONAL GRAPHENE NANORIBBONS | SEMIDEFINITE PROGRAMS | Energy gap | Orbitals | Approximation | Computation | Mathematical analysis | Density | Standards | Optimization

Journal Article

3.
Full Text
A state-specific partially internally contracted multireference coupled cluster approach

Journal of Chemical Physics, ISSN 0021-9606, 06/2011, Volume 134, Issue 21, pp. 214116 - 214116-19

A state-specific partially internally contracted multireference coupled cluster approach is presented for general complete active spaces with arbitrary number...

SINGLE-REFERENCE FORMALISM | CONFIGURATION-INTERACTION CALCULATIONS | REDUCED DENSITY-MATRICES | N-ELECTRON SYSTEMS | QUANTUM-CHEMISTRY | IRREDUCIBLE BRILLOUIN CONDITIONS | PHYSICS, ATOMIC, MOLECULAR & CHEMICAL | SYMMETRY-ADAPTED-CLUSTER | POTENTIAL-ENERGY CURVES | SIZE-EXTENSIVE MODIFICATION | EXCITED-STATES

SINGLE-REFERENCE FORMALISM | CONFIGURATION-INTERACTION CALCULATIONS | REDUCED DENSITY-MATRICES | N-ELECTRON SYSTEMS | QUANTUM-CHEMISTRY | IRREDUCIBLE BRILLOUIN CONDITIONS | PHYSICS, ATOMIC, MOLECULAR & CHEMICAL | SYMMETRY-ADAPTED-CLUSTER | POTENTIAL-ENERGY CURVES | SIZE-EXTENSIVE MODIFICATION | EXCITED-STATES

Journal Article

Journal of Chemical Physics, ISSN 0021-9606, 06/2010, Volume 132, Issue 23, pp. 234107 - 234107-8

The multireference normal order theory, introduced by Kutzelnigg and Mukherjee [ J. Chem. Phys. 107 , 432 ( 1997 )] , is defined explicitly, and an algebraic...

REDUCED DENSITY-MATRICES | N-ELECTRON SYSTEMS | IRREDUCIBLE BRILLOUIN CONDITIONS | RECONSTRUCTION | TERMS | PHYSICS, ATOMIC, MOLECULAR & CHEMICAL | LOWER-ORDER | CUMULANT EXPANSION | STATE | higher order statistics | CONTRACTED SCHRODINGER-EQUATIONS | FORMULATION

REDUCED DENSITY-MATRICES | N-ELECTRON SYSTEMS | IRREDUCIBLE BRILLOUIN CONDITIONS | RECONSTRUCTION | TERMS | PHYSICS, ATOMIC, MOLECULAR & CHEMICAL | LOWER-ORDER | CUMULANT EXPANSION | STATE | higher order statistics | CONTRACTED SCHRODINGER-EQUATIONS | FORMULATION

Journal Article

Physica Scripta, ISSN 0031-8949, 02/2017, Volume 92, Issue 2, p. 23002

We present a pedagogical introduction to the in-medium similarity renormalization group (IMSRG) framework for ab initio calculations of nuclei. The IMSRG...

shell model | ab initio nuclear structure theory | nuclear many-body theory | renormalization group | configuration interaction | N-ELECTRON SYSTEMS | CALCIUM ISOTOPES | CORE POLARIZATION | IRREDUCIBLE BRILLOUIN CONDITIONS | PHYSICS, MULTIDISCIPLINARY | MANY-BODY PROBLEM | CHARGE RADII | PERTURBATIVE ANALYSIS | FOCK SPACE | QUANTUM-CHEMISTRY | CONTRACTED SCHRODINGER-EQUATIONS

shell model | ab initio nuclear structure theory | nuclear many-body theory | renormalization group | configuration interaction | N-ELECTRON SYSTEMS | CALCIUM ISOTOPES | CORE POLARIZATION | IRREDUCIBLE BRILLOUIN CONDITIONS | PHYSICS, MULTIDISCIPLINARY | MANY-BODY PROBLEM | CHARGE RADII | PERTURBATIVE ANALYSIS | FOCK SPACE | QUANTUM-CHEMISTRY | CONTRACTED SCHRODINGER-EQUATIONS

Journal Article

Journal of Chemical Physics, ISSN 0021-9606, 11/2012, Volume 137, Issue 20, p. 204107

A generalization of the equation-of-motion coupled cluster theory is proposed, which is built upon a multireference parent state. This method is suitable for a...

CONFIGURATION-INTERACTION METHOD | REDUCED DENSITY-MATRICES | EXCITED ELECTRONIC STATES | RESPONSE FUNCTIONS | EXCITATION-ENERGIES | IRREDUCIBLE BRILLOUIN CONDITIONS | PHYSICS, ATOMIC, MOLECULAR & CHEMICAL | SYMMETRY-ADAPTED-CLUSTER | REFERENCE WAVE-FUNCTION | CONTRACTED SCHRODINGER-EQUATIONS | 2ND-ORDER PERTURBATION-THEORY | Electron states | Orbitals | Correlation | Amplitudes | Mathematical analysis | Parents | Clusters | Excitation spectra

CONFIGURATION-INTERACTION METHOD | REDUCED DENSITY-MATRICES | EXCITED ELECTRONIC STATES | RESPONSE FUNCTIONS | EXCITATION-ENERGIES | IRREDUCIBLE BRILLOUIN CONDITIONS | PHYSICS, ATOMIC, MOLECULAR & CHEMICAL | SYMMETRY-ADAPTED-CLUSTER | REFERENCE WAVE-FUNCTION | CONTRACTED SCHRODINGER-EQUATIONS | 2ND-ORDER PERTURBATION-THEORY | Electron states | Orbitals | Correlation | Amplitudes | Mathematical analysis | Parents | Clusters | Excitation spectra

Journal Article

Journal of Chemical Theory and Computation, ISSN 1549-9618, 01/2019, Volume 15, Issue 1, pp. 290 - 302

Complete active space self-consistent field (CASSCF) computations can be realized at polynomial cost via the variational optimization of the active-space...

CORRELATION-ENERGY CORRECTIONS | N-ELECTRON SYSTEMS | SELF-CONSISTENT-FIELD | SOLAR-CELLS | IRREDUCIBLE BRILLOUIN CONDITIONS | CONFIGURATION-INTERACTION | PHYSICS, ATOMIC, MOLECULAR & CHEMICAL | CHEMISTRY, PHYSICAL | SINGLET FISSION | BASIS-SETS | CONTRACTED SCHRODINGER-EQUATIONS | 2ND-ORDER PERTURBATION-THEORY | Potential energy | Density functional theory | Correlation | Polynomials | Self consistent fields | Electrons

CORRELATION-ENERGY CORRECTIONS | N-ELECTRON SYSTEMS | SELF-CONSISTENT-FIELD | SOLAR-CELLS | IRREDUCIBLE BRILLOUIN CONDITIONS | CONFIGURATION-INTERACTION | PHYSICS, ATOMIC, MOLECULAR & CHEMICAL | CHEMISTRY, PHYSICAL | SINGLET FISSION | BASIS-SETS | CONTRACTED SCHRODINGER-EQUATIONS | 2ND-ORDER PERTURBATION-THEORY | Potential energy | Density functional theory | Correlation | Polynomials | Self consistent fields | Electrons

Journal Article

JOURNAL OF CHEMICAL PHYSICS, ISSN 0021-9606, 08/2014, Volume 141, Issue 7

A new approach to density cumulant functional theory is developed that derives density cumulant N-representability conditions from an approximate Fock space...

BODY PERTURBATION-THEORY | WAVE-FUNCTIONS | QUANTUM-CHEMISTRY | IRREDUCIBLE BRILLOUIN CONDITIONS | PHYSICS, ATOMIC, MOLECULAR & CHEMICAL | ELECTRON CORRELATION THEORIES | CONTRACTED SCHRODINGER-EQUATIONS | GAUSSIAN-BASIS SETS | COUPLED-CLUSTER THEORY | SYMMETRY-BREAKING | MOLECULAR-PROPERTIES

BODY PERTURBATION-THEORY | WAVE-FUNCTIONS | QUANTUM-CHEMISTRY | IRREDUCIBLE BRILLOUIN CONDITIONS | PHYSICS, ATOMIC, MOLECULAR & CHEMICAL | ELECTRON CORRELATION THEORIES | CONTRACTED SCHRODINGER-EQUATIONS | GAUSSIAN-BASIS SETS | COUPLED-CLUSTER THEORY | SYMMETRY-BREAKING | MOLECULAR-PROPERTIES

Journal Article

Journal of Chemical Physics, ISSN 0021-9606, 06/2011, Volume 134, Issue 21, pp. 214109 - 214109-9

We propose a novel interpretation of the reduced density matrix (RDM) and its cumulant that combines linear and exponential parametrizations of the...

PERTURBATION-THEORY | ORDER | IRREDUCIBLE BRILLOUIN CONDITIONS | EXTENSIVITY | EXPANSION | TERMS | PHYSICS, ATOMIC, MOLECULAR & CHEMICAL | DETERMINING QUANTUM ENERGIES | CHEMISTRY, PHYSICAL | SYSTEMS | CONTRACTED SCHRODINGER-EQUATIONS | FORMULATION

PERTURBATION-THEORY | ORDER | IRREDUCIBLE BRILLOUIN CONDITIONS | EXTENSIVITY | EXPANSION | TERMS | PHYSICS, ATOMIC, MOLECULAR & CHEMICAL | DETERMINING QUANTUM ENERGIES | CHEMISTRY, PHYSICAL | SYSTEMS | CONTRACTED SCHRODINGER-EQUATIONS | FORMULATION

Journal Article

Accounts of Chemical Research, ISSN 0001-4842, 03/2006, Volume 39, Issue 3, pp. 207 - 215

For 50 years, progress toward the direct calculation of the ground-state two-electron reduced density matrix (2-RDM) was stymied from an inability to constrain...

N-ELECTRON SYSTEMS | VARIATIONAL METHOD | REPRESENTABILITY | IRREDUCIBLE BRILLOUIN CONDITIONS | RECONSTRUCTION | CONTRACTED SCHRODINGER-EQUATION | CUMULANT EXPANSION | APPROXIMATE SOLUTION | ENERGIES | CHEMISTRY, MULTIDISCIPLINARY | PROGRAMMING ALGORITHM | Schrodinger equation | Chemical properties | Quantum chemistry | Structure | Analysis | Electrons

N-ELECTRON SYSTEMS | VARIATIONAL METHOD | REPRESENTABILITY | IRREDUCIBLE BRILLOUIN CONDITIONS | RECONSTRUCTION | CONTRACTED SCHRODINGER-EQUATION | CUMULANT EXPANSION | APPROXIMATE SOLUTION | ENERGIES | CHEMISTRY, MULTIDISCIPLINARY | PROGRAMMING ALGORITHM | Schrodinger equation | Chemical properties | Quantum chemistry | Structure | Analysis | Electrons

Journal Article

Journal of Chemical Physics, ISSN 0021-9606, 11/2013, Volume 139, Issue 20, p. 204110

In density cumulant functional theory (DCFT) the electronic energy is evaluated from the one-particle density matrix and two-particle density cumulant,...

BODY PERTURBATION-THEORY | WAVE-FUNCTIONS | IRREDUCIBLE BRILLOUIN CONDITIONS | CORRELATED MOLECULAR CALCULATIONS | CANONICAL TRANSFORMATION THEORY | MANY-ELECTRON THEORY | PHYSICS, ATOMIC, MOLECULAR & CHEMICAL | CONTRACTED SCHRODINGER-EQUATION | ANALYTIC ENERGY DERIVATIVES | GAUSSIAN-BASIS SETS | COUPLED-CLUSTER THEORY | DENSITY | PARTICLES | INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY | RELAXATION | MATHEMATICAL METHODS AND COMPUTING | DENSITY MATRIX | WAVE FUNCTIONS

BODY PERTURBATION-THEORY | WAVE-FUNCTIONS | IRREDUCIBLE BRILLOUIN CONDITIONS | CORRELATED MOLECULAR CALCULATIONS | CANONICAL TRANSFORMATION THEORY | MANY-ELECTRON THEORY | PHYSICS, ATOMIC, MOLECULAR & CHEMICAL | CONTRACTED SCHRODINGER-EQUATION | ANALYTIC ENERGY DERIVATIVES | GAUSSIAN-BASIS SETS | COUPLED-CLUSTER THEORY | DENSITY | PARTICLES | INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY | RELAXATION | MATHEMATICAL METHODS AND COMPUTING | DENSITY MATRIX | WAVE FUNCTIONS

Journal Article

Computational and Theoretical Chemistry, ISSN 2210-271X, 01/2013, Volume 1003, pp. 62 - 70

â–º We show the notion of generalized antisymmetrized product, generalized normal ordering (GNO) and cumulants. â–º We show that all cumulants with rank greater...

Cumulants | Generalized normal ordering | Internally Contracted MRCC | IRREDUCIBLE BRILLOUIN CONDITIONS | THEOREM | TERMS | CHEMISTRY, PHYSICAL | REDUCED DENSITY-MATRICES | REPRESENTABILITY | SYSTEMS | CONTRACTED SCHRODINGER-EQUATIONS | ENERGIES | IONIZATION | COUPLED-CLUSTER THEORY

Cumulants | Generalized normal ordering | Internally Contracted MRCC | IRREDUCIBLE BRILLOUIN CONDITIONS | THEOREM | TERMS | CHEMISTRY, PHYSICAL | REDUCED DENSITY-MATRICES | REPRESENTABILITY | SYSTEMS | CONTRACTED SCHRODINGER-EQUATIONS | ENERGIES | IONIZATION | COUPLED-CLUSTER THEORY

Journal Article

Physical Review A - Atomic, Molecular, and Optical Physics, ISSN 1050-2947, 02/2007, Volume 75, Issue 2

A recent advance in the theory of the contracted Schrodinger equation (CSE), in which only the anti-Hermitian part of the equation is solved, permits the...

PERTURBATION-THEORY | N-ELECTRON SYSTEMS | WAVE-FUNCTIONS | VARIATIONAL METHOD | IRREDUCIBLE BRILLOUIN CONDITIONS | MANY-BODY PROBLEM | PHYSICS, ATOMIC, MOLECULAR & CHEMICAL | DETERMINING QUANTUM ENERGIES | LOWER-ORDER | CUMULANT EXPANSION | APPROXIMATE SOLUTION | OPTICS

PERTURBATION-THEORY | N-ELECTRON SYSTEMS | WAVE-FUNCTIONS | VARIATIONAL METHOD | IRREDUCIBLE BRILLOUIN CONDITIONS | MANY-BODY PROBLEM | PHYSICS, ATOMIC, MOLECULAR & CHEMICAL | DETERMINING QUANTUM ENERGIES | LOWER-ORDER | CUMULANT EXPANSION | APPROXIMATE SOLUTION | OPTICS

Journal Article

Physical Review A - Atomic, Molecular, and Optical Physics, ISSN 1050-2947, 08/2009, Volume 80, Issue 2

Direct calculation of the ground-state two-electron reduced density matrix (2-RDM) and its energy has recently been achieved for many-electron atoms and...

WAVE-FUNCTIONS | IRREDUCIBLE BRILLOUIN CONDITIONS | CONFIGURATION-INTERACTION | PHYSICS, ATOMIC, MOLECULAR & CHEMICAL | DETERMINING QUANTUM ENERGIES | LOWER-ORDER | CUMULANT EXPANSION | SYSTEMS | APPROXIMATE SOLUTION | BASIS-SETS | OPTICS | GEOMETRY

WAVE-FUNCTIONS | IRREDUCIBLE BRILLOUIN CONDITIONS | CONFIGURATION-INTERACTION | PHYSICS, ATOMIC, MOLECULAR & CHEMICAL | DETERMINING QUANTUM ENERGIES | LOWER-ORDER | CUMULANT EXPANSION | SYSTEMS | APPROXIMATE SOLUTION | BASIS-SETS | OPTICS | GEOMETRY

Journal Article

Chemical Physics, ISSN 0301-0104, 06/2012, Volume 401, pp. 50 - 61

The theory of reduced density matrix cumulants is rephrased into a form consistent with standard statistical concepts, thereby baring the meaning of these...

Sodium clusters | Nitrogen dissociation | Cumulants | Multireference | Transition metal complex | N-ELECTRON SYSTEMS | IRREDUCIBLE BRILLOUIN CONDITIONS | REFERENCE STATE | PHYSICS, ATOMIC, MOLECULAR & CHEMICAL | DETERMINING QUANTUM ENERGIES | CHEMISTRY, PHYSICAL | COUPLED-CLUSTER APPROACH | WAVE-FUNCTIONS | REPRESENTABILITY | EXPANSION | APPROXIMATE SOLUTION | CONTRACTED SCHRODINGER-EQUATIONS

Sodium clusters | Nitrogen dissociation | Cumulants | Multireference | Transition metal complex | N-ELECTRON SYSTEMS | IRREDUCIBLE BRILLOUIN CONDITIONS | REFERENCE STATE | PHYSICS, ATOMIC, MOLECULAR & CHEMICAL | DETERMINING QUANTUM ENERGIES | CHEMISTRY, PHYSICAL | COUPLED-CLUSTER APPROACH | WAVE-FUNCTIONS | REPRESENTABILITY | EXPANSION | APPROXIMATE SOLUTION | CONTRACTED SCHRODINGER-EQUATIONS

Journal Article

Journal of Chemical Theory and Computation, ISSN 1549-9618, 06/2014, Volume 10, Issue 6, pp. 2389 - 2398

We present an extensive benchmark study of density cumulant functional theory (DCFT) for thermochemistry and kinetics of closed- and open-shell molecules. The...

IRREDUCIBLE BRILLOUIN CONDITIONS | CORRELATED MOLECULAR CALCULATIONS | PLESSET PERTURBATION-THEORY | PHYSICS, ATOMIC, MOLECULAR & CHEMICAL | FERMION SYSTEMS | CHEMISTRY, PHYSICAL | 2 LOWEST STATES | CONTRACTED SCHRODINGER-EQUATIONS | ELECTRON-PAIR APPROXIMATION | GAUSSIAN-BASIS SETS | COUPLED-CLUSTER THEORY | NATURAL ORBITALS

IRREDUCIBLE BRILLOUIN CONDITIONS | CORRELATED MOLECULAR CALCULATIONS | PLESSET PERTURBATION-THEORY | PHYSICS, ATOMIC, MOLECULAR & CHEMICAL | FERMION SYSTEMS | CHEMISTRY, PHYSICAL | 2 LOWEST STATES | CONTRACTED SCHRODINGER-EQUATIONS | ELECTRON-PAIR APPROXIMATION | GAUSSIAN-BASIS SETS | COUPLED-CLUSTER THEORY | NATURAL ORBITALS

Journal Article

Journal of Chemical Physics, ISSN 0021-9606, 01/2013, Volume 138, Issue 2, p. 024107

Density cumulant functional theory (DCFT) is a theory that, in principle, can compute energies and properties exactly without a wavefunction. To accomplish...

N-ELECTRON SYSTEMS | WAVE-FUNCTIONS | IRREDUCIBLE BRILLOUIN CONDITIONS | CORRELATED MOLECULAR CALCULATIONS | CANONICAL TRANSFORMATION THEORY | PHYSICS, ATOMIC, MOLECULAR & CHEMICAL | DETERMINING QUANTUM ENERGIES | CHEMISTRY | CONTRACTED SCHRODINGER-EQUATION | GAUSSIAN-BASIS SETS | COUPLED-CLUSTER THEORY

N-ELECTRON SYSTEMS | WAVE-FUNCTIONS | IRREDUCIBLE BRILLOUIN CONDITIONS | CORRELATED MOLECULAR CALCULATIONS | CANONICAL TRANSFORMATION THEORY | PHYSICS, ATOMIC, MOLECULAR & CHEMICAL | DETERMINING QUANTUM ENERGIES | CHEMISTRY | CONTRACTED SCHRODINGER-EQUATION | GAUSSIAN-BASIS SETS | COUPLED-CLUSTER THEORY

Journal Article

Journal of Chemical Physics, ISSN 0021-9606, 05/2007, Volume 126, Issue 18, pp. 184101 - 184101-9

Two-electron reduced density matrices (2-RDMs) have recently been directly determined from the solution of the anti-Hermitian contracted SchrÃ¶dinger equation...

WAVE-FUNCTIONS | VARIATIONAL METHOD | REPRESENTABILITY | IRREDUCIBLE BRILLOUIN CONDITIONS | PHYSICS, ATOMIC, MOLECULAR & CHEMICAL | DETERMINING QUANTUM ENERGIES | LOWER-ORDER | CUMULANT EXPANSION | APPROXIMATE SOLUTION | ELECTRONIC-STRUCTURE CALCULATIONS | SURFACES | Quantum Theory | Algorithms | Energy Transfer | Models, Chemical | Computer Simulation | Electrons

WAVE-FUNCTIONS | VARIATIONAL METHOD | REPRESENTABILITY | IRREDUCIBLE BRILLOUIN CONDITIONS | PHYSICS, ATOMIC, MOLECULAR & CHEMICAL | DETERMINING QUANTUM ENERGIES | LOWER-ORDER | CUMULANT EXPANSION | APPROXIMATE SOLUTION | ELECTRONIC-STRUCTURE CALCULATIONS | SURFACES | Quantum Theory | Algorithms | Energy Transfer | Models, Chemical | Computer Simulation | Electrons

Journal Article