title: Accuracy and efficiency of atomic basis set methods versus plane wave calculations with ultrasoft pseudopotentials for DNA base molecules.
abstract: Recent results from Preuss et al. (J Comput Chem 2004, 25, 112) on DNA base molecules, obtained by plane wave density functional calculations using ultrasoft pseudopotentials, are compared with calculations using Gaussian basis sets. Bond lengths and angles agree closely, but dihedral angles and vibrational frequencies show significant differences. The Gaussian basis calculations are at least an order of magnitude more efficient than the plane wave/ultrasoft pseudopotential calculations at a similar level of accuracy; the advantage is even larger if the Fourier Transform Coulomb method is used. To obtain definite benchmark values, the geometries of the four DNA bases were optimized at the MP2 level with large basis sets, up to cc-pVQZ and aug-cc-pVTZ.
authors.affiliation: Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas 72701, USA. pulay@uark.edu
authors.forename: Peter
authors.initials: P
authors.lastname: Pulay
authors.forename: Svein
authors.initials: S
authors.lastname: Saebo
authors.forename: Massimo
authors.initials: M
authors.lastname: Malagoli
authors.forename: Jon
authors.initials: J
authors.lastname: Baker
mesh_terms: D004247:DNA / Q000737:chemistry*; D008958:Models, Molecular; D011687:Purines / Q000737:chemistry*; D011743:Pyrimidines / Q000737:chemistry*; D013816:Thermodynamics
chemical_list: D011687:Purines; D011743:Pyrimidines; D004247:DNA