Assessing the performance of density functional theory on metal-salen catalysts: 3d6 and 4d6 metal centers

PHYS 583

Tait Takatani, tait.takatani@gatech.edu, John S. Sears, john.sears@chemistry.gatech.edu, and C. David Sherrill, sherrill@chemistry.gatech.edu. School of Chemistry and Biochemistry, Georgia Institute of Technology, Atlanta, GA 30332-0400
As part of a systematic study of metal-salen catalysts, model systems containing metal centers with six electrons have been considered for three 3d6 [Fe(II), Co(III), and Ni(IV)] and three 4d6 [Ru(II), Rh(III), and Pd(IV)] species. The Co(III) and the Ru(II) species have been shown to effectively catalyze the hydrolytic kinetic resolution of terminal epoxides and olefin metathesis, respectively. The state averaged complete active space self consistent field (SA-CASSCF) method with a minimal active space was used to obtain low-lying singlet, triplet and quintet state energies and corresponding optimized geometries for the systems studied. Density functional theory (DFT) with the popular B3LYP and BP86 functionals, in comparison with the more robust SA-CASSCF method, shows significant and unsystematic errors in the energetic ordering of the electronic states and the energy gaps between them. DFT methods do, however, characterize the geometries rather well with root mean squared deviations of only tenths of Angstroms.
 

PHYS Poster Session - Computational Spectroscopy and Reaction Dynamics
7:30 PM-10:00 PM, Wednesday, April 9, 2008 Morial Convention Center -- Hall A, Poster

Division of Physical Chemistry

The 235th ACS National Meeting, New Orleans, LA, April 6-10, 2008