Density functional theory cobalt complexes

Freedman TB, Cao XL, Young DA et al (2002) Density functional theory calculations of vibrational circular dichroism in transition metal complexes Identification of solution conformations and mode of chloride ion association for (+)-tris(ethylenediaminato)cobalt (III). J Phys Chem A 106 3560-3565... 

Theoretical aspects of the Co(NHj)g system have been described recently by Endres et al. They considered the involvement of various possible spin states of Co(III) and Co(II) and concluded that the most favorable exchange occurs between the ground state of Co(III), and a spin-excited state of Co(II), They find that the latter is stabilized by Jahn-Teller distortion, a factor which was not considered in earlier work where it was concluded that the reactants were electronic ground states for both oxidation states. The issue of spin-state effects in other cobalt complexes is discussed below. Endres et al. also have provided a brief summary of the weaknesses of Density Functional Theory when applied to such systems. If the spin-state change prediction is correct, then the agreement between calculated and observed values for the Co(NHj)5 system in Table 6.1 could be fortuitous. 

Density-Functional Theory Investigation of the Geometric, Energetic, and Optical Properties of the Cobalt(II)tris(2,2 -bipyridine) Complex in the High-Spin and the... 

Recently, the [64-2] cycloaddition of CHT with internal alkynes was described with rhodium catalysts (Scheme 8.37) [58]. The optimal catalytic system consisted of a combination of [Rh(cod)Cl]2, Cul, and PPh3. A mechanism involving rhodacycles similar to the one reported with cobalt complexes [55] was proposed and supported by density functional theory (DFT) calculations. 

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