A pseudoatom approach to molecular truncation: Application in ab initio MBPT methods

Decarlos E. Taylor, Steven W. Bunte, Keith A Runge

Research output: Contribution to journalArticle

6 Citations (Scopus)

Abstract

In this paper, we test the performance of the molecular truncation method of Mallik et al., 1 which was originally applied at the semiempirical NDDO level, in ab initio MBPT methods. Pseudoatoms developed for the replacement of -OCH 3 and -OCH 2CH 3 functional groups are used in optimizations of selected clusters, and the resulting geometries are compared to reference values taken from the full molecules. It is shown that the pseudoatoms, which consist of parametrized effective core potentials for the nearest neighbor interactions and an external charge field for long-range Coulomb effects, perform well at the MP2 and CCSD levels of theory for the suite of molecules to which they were applied. Representative timings for some of the pseudoatom-terminated clusters are presented, and it is seen that there is a significant reduction in computational time, yet the geometric configurations and deprotonation energies of the pseudoatom-terminated clusters are comparable to the more computationally expensive all-atom molecules.

Original languageEnglish (US)
Pages (from-to)6279-6284
Number of pages6
JournalJournal of Physical Chemistry A
Volume110
Issue number19
DOIs
StatePublished - May 18 2006
Externally publishedYes

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Molecules
approximation
molecules
Deprotonation
Functional groups
time measurement
Atoms
optimization
Geometry
geometry
configurations
atoms
interactions
energy

ASJC Scopus subject areas

  • Physical and Theoretical Chemistry

Cite this

A pseudoatom approach to molecular truncation : Application in ab initio MBPT methods. / Taylor, Decarlos E.; Bunte, Steven W.; Runge, Keith A.

In: Journal of Physical Chemistry A, Vol. 110, No. 19, 18.05.2006, p. 6279-6284.

Research output: Contribution to journalArticle

Taylor, Decarlos E. ; Bunte, Steven W. ; Runge, Keith A. / A pseudoatom approach to molecular truncation : Application in ab initio MBPT methods. In: Journal of Physical Chemistry A. 2006 ; Vol. 110, No. 19. pp. 6279-6284.
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