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Basis set effects on calculated geometries: 6‐311++G** vs. aug‐cc‐pVDZ
Author(s) -
Wiberg Kenneth B.
Publication year - 2004
Publication title -
journal of computational chemistry
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.907
H-Index - 188
eISSN - 1096-987X
pISSN - 0192-8651
DOI - 10.1002/jcc.20058
Subject(s) - basis set , basis (linear algebra) , computation , set (abstract data type) , series (stratigraphy) , computational chemistry , mathematics , physics , atomic physics , molecule , statistical physics , chemistry , quantum mechanics , geometry , computer science , algorithm , geology , paleontology , programming language
The effect of basis sets on MP2 and CCSD calculated geometries has been investigated for a series of small organic molecules with two to four nonhydrogen atoms. Whereas 6‐311++G** usually leads to satisfactory structures, this was not true with aug‐cc‐pVDZ, although it uses more basis functions than the former set. In addition, the smaller 6‐311++G** invariably leads to lower calculated energies than aug‐cc‐pVDZ. With a given basis set, CCSD gives more satisfactory calculated geometries than MP2, but with a much greater computation time. For the compounds in this report, B3LYP/6‐311++G** is quite effective in giving satisfactory calculated geometries at a relatively small computational cost. © 2004 Wiley Periodicals, Inc. J Comput Chem 25: 1342–1346, 2004