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Lithium-pyrazole-3,4,5-tricarbonitrile: Ion Pairing and Lithium Ion Affinity Studies
journal contribution
posted on 2003-11-27, 00:00 authored by Henrik Markusson, Stéphane Béranger, Patrik Johansson, Michel Armand, Per JacobssonNegative charge stabilized by ring delocalization on five-membered rings is a practical and theoretically
interesting alternative to conventional fluorine-based anions. Coordination of the lithium cation to the pyrazole-3,4,5-tricarbonitrile (PATC) anion was studied using vibrational spectroscopy (Raman and IR) and ab initio
SCF-MO Hartree−Fock (HF) calculations. Four 1:1 ion pair geometries were found, one being energetically
more stable. By comparing theoretical spectra with both IR and Raman spectra of salt solutions, it was found
that the lithium ion favors bidentate coordination to the ring nitrogen atoms, as suggested by the binding
energies. Finally, comparisons were made with previously calculated coordination strengths for other similar
lithium anion 1:1 systems.