title: Accurate modeling of spin-state energetics in spin-crossover systems with modern density functional theory.
abstract: The energies of different spin multiplicities of a range of iron complexes are computed using modern density functional theory (DFT) methods of the generalized gradient approximation (GGA; BP86 and OPBE), meta-GGA (TPSS), hybrid meta-GGA (TPSSh), hybrid (B3LYP), and double-hybrid (B2PLYP) types. It is shown that so far only the double-hybrid density functional B2PLYP, in conjunction with large and flexible basis sets (def2-QZVPP), is able to provide qualitatively correct results of spin-state energetics for the investigated non-spin-crossover complexes. An energy difference of -6 to 0 kcal/mol is proposed to be indicative of spin-crossover behavior.
authors.affiliation: Lehrstuhl für Theoretische Chemie, Institut für Physikalische und Theoretische Chemie, Universität Bonn, Wegelerstrasse 12, D-53115 Bonn, Germany.
authors.forename: Shengfa
authors.initials: S
authors.lastname: Ye
authors.forename: Frank
authors.initials: F
authors.lastname: Neese
mesh_terms: D003198:Computer Simulation; D005290:Ferric Compounds / Q000737:chemistry*; D008956:Models, Chemical
chemical_list: D005290:Ferric Compounds