257623-52-2Relevant academic research and scientific papers
Effect of a metal ion on intramolecular spin exchange in spin-labeled complexes
Kokorin,Evstiferov,Grigor'ev,Reznikov,Grampp
, p. 1982 - 1986 (2007/10/03)
The characteristic features of intramolecular spin exchange in 14 complexes of AgI, HgII, NiII, PdII, PtII, AuIII, and PtIV with spin-labeled ligands were studied by ESR spectroscopy. The measured values of the exchange integral |J and the differences between the enthalpies of the efficient conformations (ΔH) were compared with the electronic polarization (refraction) Rf of the NiII, PdII, and PtII ions and Klopman's rigidity parameters σK, which characterize the total polarazibility of the ions and the degree of covalence of the bond between the metal atom and the donor atom of the ligand, respectively. Delocalization of the electron spin density and the efficiency of spin exchange are determined by the relative contributions of the s, p, and d orbitals, which produce the overlap integral of wave functions, |J|, and by the geometric features of the coordination polyhedron, which affect the mutual orientation of the N-O fragments.
