Noniterative local second order Mo/ller{endash}Plesset theory: Convergence with local correlation space
Abstract
We extend our noniterative local correlation method [P. E. Maslen and M. HeadGordon, Chem. Phys. Lett., {bold 283}, 102 (1998)] by defining a hierarchy of local spaces, ranging from small to large. The accuracy of the local method is then examined as a function of the size of the local space. A medium size local space recovers 98{percent} of the MP2 correlation energy, and reproduces fine details of the potential energy surface such as rotational barriers with an RMS error of 0.2 kcal/mol and a maximum error of 0.4 kcal/mol. A large local space recovers 99.5{percent} of the correlation energy and yields rotational barriers with a RMS error of 0.05 kcal/mol and a maximum error of 0.1 kcal/mol, at significantly increased computational cost. {copyright} {ital 1998 American Institute of Physics.}
 Authors:
 Department of Chemistry, University of California, Berkeley, Berkeley, California, 94720 (United States)
 Publication Date:
 OSTI Identifier:
 298604
 Resource Type:
 Journal Article
 Resource Relation:
 Journal Name: Journal of Chemical Physics; Journal Volume: 109; Journal Issue: 17; Other Information: PBD: Nov 1998
 Country of Publication:
 United States
 Language:
 English
 Subject:
 66 PHYSICS; PERTURBATION THEORY; ELECTRONIC STRUCTURE; MOLECULAR ORBITAL METHOD; ELECTRON CORRELATION
Citation Formats
Maslen, P.E., and HeadGordon, M.. Noniterative local second order Mo/ller{endash}Plesset theory: Convergence with local correlation space. United States: N. p., 1998.
Web. doi:10.1063/1.477392.
Maslen, P.E., & HeadGordon, M.. Noniterative local second order Mo/ller{endash}Plesset theory: Convergence with local correlation space. United States. doi:10.1063/1.477392.
Maslen, P.E., and HeadGordon, M.. 1998.
"Noniterative local second order Mo/ller{endash}Plesset theory: Convergence with local correlation space". United States.
doi:10.1063/1.477392.
@article{osti_298604,
title = {Noniterative local second order Mo/ller{endash}Plesset theory: Convergence with local correlation space},
author = {Maslen, P.E. and HeadGordon, M.},
abstractNote = {We extend our noniterative local correlation method [P. E. Maslen and M. HeadGordon, Chem. Phys. Lett., {bold 283}, 102 (1998)] by defining a hierarchy of local spaces, ranging from small to large. The accuracy of the local method is then examined as a function of the size of the local space. A medium size local space recovers 98{percent} of the MP2 correlation energy, and reproduces fine details of the potential energy surface such as rotational barriers with an RMS error of 0.2 kcal/mol and a maximum error of 0.4 kcal/mol. A large local space recovers 99.5{percent} of the correlation energy and yields rotational barriers with a RMS error of 0.05 kcal/mol and a maximum error of 0.1 kcal/mol, at significantly increased computational cost. {copyright} {ital 1998 American Institute of Physics.}},
doi = {10.1063/1.477392},
journal = {Journal of Chemical Physics},
number = 17,
volume = 109,
place = {United States},
year = 1998,
month =
}

We perform distributed calculations of the MP2 and EN2 corrections to the charge density of a lot of molecules. A heterogeneous cluster of IBM RS/600 and Silicon Graphics workstations is used. These networkbased distributed concurrent calculations are developed with the {bold P}arallel {bold V}irtual {bold M}achine system of the Oak Ridge National Laboratory, with the ETHERNET IP mode and, for the RS/6000s, the SOCC IP mode. (AIP) {copyright}{ital 1995 American Institute of Physics}

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