%0 Journal Article
%A Islam, Shahidul M.
%A Huelin, Stephanie D.
%A Dawe, Margot
%A Poirier, Raymond A.
%D 2008
%T Comparison of the Standard 6-31G and Binning-Curtiss
Basis Sets for Third Row Elements
%U https://acs.figshare.com/articles/journal_contribution/Comparison_of_the_Standard_6_31G_and_Binning_Curtiss_Basis_Sets_for_Third_Row_Elements/2964187
%R 10.1021/ct700224j.s002
%2 https://ndownloader.figshare.com/files/4663297
%K BC
%K CH 3SeH SiH 3SeH CH 3AsH SiH 3AsH CH 3GeH
%K MAD
%K set
%K frequency
%K HF
%K B 3LYP levels
%K row elements
%K cm
%K basis
%K Third Row ElementsAb initio calculations
%K G 3MP enthalpies
%K row elements geometries
%K G 3MP values
%X Ab initio calculations were carried out for isogyric reactions involving the third row
elements, Ga, Ge, As, Se, and Br. Geometries of all the reactants and products were optimized
at the HF, MP2, and B3LYP levels of theory using the 6-31G(d) and 6-31G(d,p) basis sets. For
molecules containing third row elements geometries, frequencies and thermodynamic properties
were calculated using both the standard 6-31G and the Binning-Curtiss (BC6-31G) basis sets.
In order to determine the performance of these basis sets, the calculated thermodynamic
properties were compared to G3MP2 values and where possible to experimental values.
Geometries and frequencies calculated with the standard 6-31G and the BC6-31G basis sets
were found to differ significantly. Frequencies calculated with the standard 6-31G basis set were
generally in better agreement with the experimental values (MAD=40.1 cm-1 at B3LYP/6-31G(d,p) and 94.2 cm-1 at MP2/6-31G(d,p) for unscaled frequencies and 29.6 cm-1 and 24.4 cm-1,
respectively, for scaled frequencies). For all the reactions investigated, the thermodynamic
properties calculated with the standard 6-31G basis set were found to consistently be in better
agreement with the G3MP2 and the available experimental results. However, the BC6-31G basis
set performs poorly for the reactions involving both second and third row elements. Since, in
general, the standard 6-31G basis set performs well for all the reactions, we recommend that
the standard 6-31G basis set be used for calculations involving third row elements. Using G3MP2
enthalpies of reaction and available experimental heats of formation (ΔHf), previously unknown
ΔHf for CH3SeH, SiH3SeH, CH3AsH2, SiH3AsH2, CH3GeH3, and SiH3GeH3 were found to be
18.3, 18.0, 38.4, 82.4, 41.9, and 117.4 kJ mol-1, respectively.
%I ACS Publications