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Title: Electronic structure of (MePh 3 P) 2 [Ni II (bdtCl 2 ) 2 ]·2(CH 3 ) 2 SO and (MePh 3 P)[Ni III (bdtCl 2 ) 2 ] (bdtCl 2 = 3,6-dichlorobenzene-1,2-dithiolate)
High-resolution X-ray diffraction experiments, theoretical calculations and atom-specific X-ray absorption experiments were used to investigate two nickel complexes, (MePh 3 P) 2 [Ni II (bdtCl 2 ) 2 ]·2(CH 3 ) 2 SO [complex (1)] and (MePh 3 P)[Ni III (bdtCl 2 ) 2 ] [complex (2)]. Combining the techniques of nickel K - and sulfur K -edge X-ray absorption spectroscopy with high-resolution X-ray charge density modeling, together with theoretical calculations, the actual oxidation states of the central Ni atoms in these two complexes are investigated. Ni ions in two complexes are clearly in different oxidation states: the Ni ion of complex (1) is formally Ni II ; that of complex (2) should be formally Ni III , yet it is best described as a combination of Ni 2+ and Ni 3+ , due to the involvement of the non-innocent ligand in the Ni— L bond. A detailed description of Ni—S bond character (σ,π) is presented.
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Acta Crystallographica Section B Structural Science, Crystal Engineering and Materials
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National Science Foundation
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