Molecular physics and chemistry applications of quantum Monte Carlo
We discuss recent work with the diffusion quantum Monte Carlo (QMC) method in its application to molecular systems. The formal correspondence of the imaginary time Schroedinger equation to a diffusion equation allows one to calculate quantum mechanical expectation values as Monte Carlo averages over an ensemble of random walks. We report work on atomic and molecular total energies, as well as properties including electron affinities, binding energies, reaction barriers, and moments of the electronic charge distribution. A brief discussion is given on how standard QMC must be modified for calculating properties. Calculated energies and properties are presented for a number of molecular systems, including He, F, F , H2, N, and N2. Recent progress in extending the basic QMC approach to the calculation of ''analytic'' (as opposed to finite-difference) derivatives of the energy is presented, together with an H2 potential-energy curve obtained using analytic derivatives. 39 refs., 1 fig., 2 tabs.
- Research Organization:
- Lawrence Berkeley Lab., CA (USA)
- DOE Contract Number:
- AC03-76SF00098
- OSTI ID:
- 6285956
- Report Number(s):
- LBL-20488; CONF-8509213-3; ON: DE86006273
- Resource Relation:
- Conference: Frontiers of quantum Monte Carlo conference, Los Alamos, NM, USA, 3 Sep 1985
- Country of Publication:
- United States
- Language:
- English
Similar Records
Quantum chemistry by quantum Monte Carlo: beyond ground-state energy calculations
Quantum Monte Carlo for molecules. Annual summary report, January 1-December 31, 1985, Annual summary report, 1 January-31 December 1985
Related Subjects
71 CLASSICAL AND QUANTUM MECHANICS
GENERAL PHYSICS
FLUORINE
ELECTRONIC STRUCTURE
FLUORINE IONS
HELIUM
HYDROGEN
MOLECULAR STRUCTURE
MONTE CARLO METHOD
QUANTUM MECHANICS
NITROGEN
DIFFUSION
QUADRUPOLE MOMENTS
SCHROEDINGER EQUATION
THEORETICAL DATA
CHARGED PARTICLES
DATA
DIFFERENTIAL EQUATIONS
ELEMENTS
EQUATIONS
FLUIDS
GASES
HALOGENS
INFORMATION
IONS
MECHANICS
NONMETALS
NUMERICAL DATA
PARTIAL DIFFERENTIAL EQUATIONS
RARE GASES
WAVE EQUATIONS
640305* - Atomic
Molecular & Chemical Physics- Atomic & Molecular Theory- (-1987)
657002 - Theoretical & Mathematical Physics- Classical & Quantum Mechanics