Cobalt complexes spin-crossover effects

These studies raised several fundamental questions about the effects of pincer substituents on the overall electronic structure of the resulting cobalt halide or alkyl compound. First, why are the electronic stractures of N-aryl and N-alkyl substituted bis(imino)pyridine cobalt chloride complexes different. Second, why for the N-alkyl derivatives is the chloride compound spin crossover and the methyl diamagnetic. What role does the distortion of the hgand play on the overall electronic structure ... 

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