Implementation and Benchmark Tests of the DFTB Method and Its Application in the ONIOM Method
2009 (English)In: International Journal of Quantum Chemistry, ISSN 0020-7608, E-ISSN 1097-461X, Vol. 109, no 9, 1841-1854 p.Article in journal (Refereed) Published
We present the theoretical and implementation details of the DFTB method with analytical gradients into the Gaussian package. SCF optimization performance with DIIS method is compared with modified Broyden method and Anderson methods, from which DIIS method is to be preferred. The number of geometry optimization steps can be significantly decreased with the Berny algorithm compared to the conjugated gradient method. From the comparison of geometry parameters as well as trends in the change of HOMO and LUMO energies, the results show clearly that DFTB can reproduce values obtained at the B3LYP/6-31G(d) level well. We also investigated the DFTB method as the low level quantum mechanical (QM) method in an ONIOM (QM:QM') description for all amino acid model system and found DFTB promising as a method to describe polarization and charge-transfer effects in large systems. (c) 2009 Wiley Periodicals, Inc. Int J Quantum Chem 109: 1841-1854, 2009
Place, publisher, year, edition, pages
2009. Vol. 109, no 9, 1841-1854 p.
DFTB, density functional tight binding, ONIOM
IdentifiersURN: urn:nbn:se:uu:diva-145476DOI: 10.1002/qua.22002OAI: oai:DiVA.org:uu-145476DiVA: diva2:396507
Times Cited: 12011-02-102011-02-092016-04-22