A density functional study of the spin state energetics of polypyrazolylborato complexes of first-row transition
M Gruden-Pavlović1, S Stepanović, M Perić
1Faculty of Chemistry, University of Belgrade, Studentski trg 12-16, Belgrade, Serbia. gmaja@chem.bg.ac.rs.
Abstract:
Density Functional Theory (DFT) was used to analyse and explain spin state energetics of first-row transition metals (Mn(II), Fe(II), Co(II); Cr(III), Mn(III), Fe(III), Co(III); Mn(IV)) in polypyrazolylborato complexes. We explored the effects of substitutions at the 3 and 5 positions of the pyrazolyl rings, as well as the influence of Jahn-Teller (JT) distortions on spin-state switching. Although the stabilizations due to JT distortion are sometimes substantial, this does not lead to switching of the spin ground-state. On the other hand, electron withdrawing or donating substituents do lead to significant changes in the spin-crossover (SCO) properties of the investigated complexes.
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