skip to main content
OSTI.GOV title logo U.S. Department of Energy
Office of Scientific and Technical Information

Title: Benchmark atomization energy of ethane : importance of accurate zero-point vibrational energies and diagonal Born-Oppenheimer corrections for a 'simple' organic molecule.

Abstract

A benchmark calculation of the atomization energy of the 'simple' organic molecule C2H6 (ethane) has been carried out by means of W4 theory. While the molecule is straightforward in terms of one-particle and n-particle basis set convergence, its large zero-point vibrational energy (and anharmonic correction thereto) and nontrivial diagonal Born-Oppenheimer correction (DBOC) represent interesting challenges. For the W4 set of molecules and C2H6, we show that DBOCs to the total atomization energy are systematically overestimated at the SCF level, and that the correlation correction converges very rapidly with the basis set. Thus, even at the CISD/cc-pVDZ level, useful correlation corrections to the DBOC are obtained. When applying such a correction, overall agreement with experiment was only marginally improved, but a more significant improvement is seen when hydrogen-containing systems are considered in isolation. We conclude that for closed-shell organic molecules, the greatest obstacles to highly accurate computational thermochemistry may not lie in the solution of the clamped-nuclei Schroedinger equation, but rather in the zero-point vibrational energy and the diagonal Born-Oppenheimer correction.

Authors:
; ;
Publication Date:
Research Org.:
Argonne National Lab. (ANL), Argonne, IL (United States)
Sponsoring Org.:
USDOE Office of Science (SC)
OSTI Identifier:
914906
Report Number(s):
ANL/CHM/JA-58253
TRN: US200817%%7
DOE Contract Number:  
DE-AC02-06CH11357
Resource Type:
Journal Article
Journal Name:
J. Mol. Struct. THEOCHEM
Additional Journal Information:
Journal Volume: 811; Journal Issue: 1-3 ; Jun. 1, 2007
Country of Publication:
United States
Language:
ENGLISH
Subject:
37 INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL CHEMISTRY; ATOMIZATION; ETHANE; VIBRATIONAL STATES; BORN-OPPENHEIMER APPROXIMATION; CORRECTIONS; SCHROEDINGER EQUATION

Citation Formats

Karton, A, Martin, J M. L., Ruscic, B, Chemistry, and Weizmann Institute of Science. Benchmark atomization energy of ethane : importance of accurate zero-point vibrational energies and diagonal Born-Oppenheimer corrections for a 'simple' organic molecule.. United States: N. p., 2007. Web. doi:10.1016/j.theochem.2007.01.013.
Karton, A, Martin, J M. L., Ruscic, B, Chemistry, & Weizmann Institute of Science. Benchmark atomization energy of ethane : importance of accurate zero-point vibrational energies and diagonal Born-Oppenheimer corrections for a 'simple' organic molecule.. United States. https://doi.org/10.1016/j.theochem.2007.01.013
Karton, A, Martin, J M. L., Ruscic, B, Chemistry, and Weizmann Institute of Science. 2007. "Benchmark atomization energy of ethane : importance of accurate zero-point vibrational energies and diagonal Born-Oppenheimer corrections for a 'simple' organic molecule.". United States. https://doi.org/10.1016/j.theochem.2007.01.013.
@article{osti_914906,
title = {Benchmark atomization energy of ethane : importance of accurate zero-point vibrational energies and diagonal Born-Oppenheimer corrections for a 'simple' organic molecule.},
author = {Karton, A and Martin, J M. L. and Ruscic, B and Chemistry and Weizmann Institute of Science},
abstractNote = {A benchmark calculation of the atomization energy of the 'simple' organic molecule C2H6 (ethane) has been carried out by means of W4 theory. While the molecule is straightforward in terms of one-particle and n-particle basis set convergence, its large zero-point vibrational energy (and anharmonic correction thereto) and nontrivial diagonal Born-Oppenheimer correction (DBOC) represent interesting challenges. For the W4 set of molecules and C2H6, we show that DBOCs to the total atomization energy are systematically overestimated at the SCF level, and that the correlation correction converges very rapidly with the basis set. Thus, even at the CISD/cc-pVDZ level, useful correlation corrections to the DBOC are obtained. When applying such a correction, overall agreement with experiment was only marginally improved, but a more significant improvement is seen when hydrogen-containing systems are considered in isolation. We conclude that for closed-shell organic molecules, the greatest obstacles to highly accurate computational thermochemistry may not lie in the solution of the clamped-nuclei Schroedinger equation, but rather in the zero-point vibrational energy and the diagonal Born-Oppenheimer correction.},
doi = {10.1016/j.theochem.2007.01.013},
url = {https://www.osti.gov/biblio/914906}, journal = {J. Mol. Struct. THEOCHEM},
number = 1-3 ; Jun. 1, 2007,
volume = 811,
place = {United States},
year = {Fri Jun 01 00:00:00 EDT 2007},
month = {Fri Jun 01 00:00:00 EDT 2007}
}