title: Assessment of the "6-31+G** + LANL2DZ" mixed basis set coupled with density functional theory methods and the effective core potential: prediction of heats of formation and ionization potentials for first-row-transition-metal complexes.
abstract: Computational chemists have long demonstrated great interest in finding ways to reliably and accurately predict the molecular properties for transition-metal-containing complexes. This study is a continuation of our validation efforts of density functional theory (DFT) methods when applied to transition-metal-containing systems (Riley, K.E.; Merz, K. M., Jr. J. Phys. Chem. 2007, 111, 6044-6053). In our previous work we examined DFT using all-electron basis sets, but approaches incorporating effective core potentials (ECPs) are effective in reducing computational expense. With this in mind, our efforts were expanded to include evaluation of the performance of the basis set derived to approximate such an approach as well on the same set of density functionals. Indeed, employing an ECP basis such as LANL2DZ (Los Alamos National Laboratory 2 double zeta) for transition metals, while using all-electron basis sets for all other non-transition-metal atoms, has become more and more popular in computations on transition-metal-containing systems. In this study, we assess the performance of 12 different DFT functionals, from the GGA (generalized gradient approximation), hybrid-GGA, meta-GGA, and hybrid-meta-GGA classes, respectively, along with the 6-31+G** + LANL2DZ (on the transition metal) mixed basis set in predicting two important molecular properties, heats of formation and ionization potentials, for 94 and 58 systems containing first-row transition metals from Ti to Zn, which are all in the third row of the periodic table. An interesting note is that the inclusion of the exact exchange term in density functional methods generally increases the accuracy of ionization potential prediction for the hybrid-GGA methods but decreases the reliability of determining the heats of formation for transition-metal-containing complexes for all hybrid density functional methods. The hybrid-GGA functional B3LYP gives the best performance in predicting the ionization potentials, while the meta-GGA functional TPSSTPSS provides the most reliable and accurate results for heat of formation calculations. TPSSTPSS, a meta-GGA functional, which was constructed from first principles and subject to known exact constraints just like in an "ab initio" way, is successful in predicting both the ionization potentials and the heats of formation for transition-metal-containing systems.
authors.affiliation: Quantum Theory Project, Department of Chemistry, University of Florida, Gainesville, Florida 32611, USA.
authors.forename: Yue
authors.initials: Y
authors.lastname: Yang
authors.forename: Michael N
authors.initials: MN
authors.lastname: Weaver
authors.forename: Kenneth M
authors.initials: KM
authors.lastname: Merz
mesh_terms: D006358:Hot Temperature; D011789:Quantum Theory; D015203:Reproducibility of Results; D013816:Thermodynamics; D028561:Transition Elements / Q000737:chemistry*
chemical_list: D028561:Transition Elements
references.citation: J Phys Chem A. 2007 Jul 12;111(27):6044-53
references.pmid: 17571862
references.citation: J Phys Chem A. 2006 Jan 19;110(2):709-16
references.pmid: 16405344
references.citation: Phys Rev B Condens Matter. 1992 Sep 15;46(11):6671-6687
references.pmid: 10002368
references.citation: Phys Rev Lett. 2003 Oct 3;91(14):146401
references.pmid: 14611541
references.citation: Curr Opin Struct Biol. 2001 Apr;11(2):217-23
references.pmid: 11297931
references.citation: Phys Rev B Condens Matter. 1988 Jan 15;37(2):785-789
references.pmid: 9944570
references.citation: J Comput Aided Mol Des. 2000 Feb;14(2):123-34
references.pmid: 10721501
references.citation: J Am Chem Soc. 2007 Feb 7;129(5):1378-85
references.pmid: 17263422
references.citation: J Chem Phys. 2007 Apr 14;126(14):144101
references.pmid: 17444695
references.citation: J Chem Phys. 2004 Apr 15;120(15):6898-911
references.pmid: 15267588
references.citation: Phys Rev A Gen Phys. 1988 Sep 15;38(6):3098-3100
references.pmid: 9900728
references.citation: Science. 1970 Apr 3;168(3927):71-7
references.pmid: 17838971
references.citation: J Chem Theory Comput. 2007;3(2):407-433
references.pmid: 19002267
references.citation: J Comput Chem. 2003 Jul 15;24(9):1009-15
references.pmid: 12759901
references.citation: J Phys Chem B. 2006 Sep 28;110(38):18787-802
references.pmid: 16986869
references.citation: J Chem Theory Comput. 2008 Jan;4(1):75-85
references.pmid: 26619981
references.citation: Science. 2002 Oct 25;298(5594):759-60
references.pmid: 12399569
references.citation: J Chem Theory Comput. 2008 Jul;4(7):1029-31
references.pmid: 26636355
references.citation: J Phys Chem A. 2005 Dec 15;109(49):11127-43
references.pmid: 16331896
references.citation: J Phys Chem A. 2005 Mar 3;109(8):1643-9
references.pmid: 16833489
references.citation: J Phys Chem A. 2005 May 19;109(19):4388-403
references.pmid: 16833770
references.citation: Phys Rev B Condens Matter. 1992 Jun 15;45(23):13244-13249
references.pmid: 10001404
references.citation: J Chem Phys. 2006 Jun 14;124(22):224105
references.pmid: 16784261
references.citation: J Chem Phys. 2006 Jan 28;124(4):044103
references.pmid: 16460145
references.citation: Phys Rev Lett. 2000 May 29;84(22):5070-3
references.pmid: 10990869
references.citation: Phys Rev Lett. 1996 Oct 28;77(18):3865-3868
references.pmid: 10062328
references.citation: J Chem Phys. 2006 Sep 28;125(12):124107
references.pmid: 17014166