What is the best density functional to describe water clusters: evaluation of widely used density functionals with various basis sets for (H2O)n (n = 1-10)

0370018 - ÚOCHB 2012 RIV DE eng J - Journal Article
Li, F. - Wang, L. - Zhao, J. - Xie, J. R. H. - Riley, Kevin Eugene - Chen, Z.
What is the best density functional to describe water clusters: evaluation of widely used density functionals with various basis sets for (H2O)n (n = 1-10).
Theoretical Chemistry Accounts. Roč. 130, 2/3 (2011), s. 341-352. ISSN 1432-881X. E-ISSN 1432-2234
Institutional research plan: CEZ:AV0Z40550506
Keywords : water cluster * density functional theory * MP2 . CCSD(T) * basis set * relative energies
Subject RIV: CF - Physical ; Theoretical Chemistry
Impact factor: 2.162, year: 2011

The geometric structures, stabilization energies, dipole moments, and vibrational frequencies of the neutral water clusters (H2O)n, with n = 1–10, were investigated using density functional theory along with a variety of exchange-correlation functionals (LDA with SVWN5 parameterization, GGA with BLYP, PW91, PBE, B3LYP, X3LYP, PBE0, PBE1W, M05-2X, M06-2X and M06-L parameterizations) as well as high-level ab initio MP2 and CCSD(T) methods. Using the MP2 and CCSD(T) results as benchmarks, the effects of exchange-correlation functionals and basis sets were carefully examined. Each functional has its advantage in certain aspects; for example, M05-2X and X3LYP yield better geometries, and the capability of these two functionals to distinguish the relative energies between isomers are more similar to MP2. The size of the splitvalence basis set (6-31G or larger), diffuse functions on the oxygen atom, and d(p) polarization on the oxygen (hydrogen) atom are crucial for an accurate description of intermolecular interaction in water clusters. The 6-31?G(2d,p) basis set is thus recommended as a compromise between computational efficiency and accuracy for structural description. We further demonstrated that the numerical basis set, TNP, performs satisfactorily in describing structural parameters of water clusters.
Permanent Link: http://hdl.handle.net/11104/0203939