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Updated: Aug 6, 2026

From Molecules to Materials: Engineering New Ionic Liquid Crystals Through Halogen Bonding
Published on: March 24, 2018
Characterization of the chloranilate(*3-) pi radical as a strong spin-coupling bridging ligand
Kil Sik Min1, Arnold L Rheingold, Antonio Dipasquale
1Department of Chemistry, University of Utah, 315 South 1400 East, Room 2124, Salt Lake City, UT 84112-0850, USA.
Abstract:
Dinuclear [(TPA)Co(II)(CA2-)Co(II)(TPA)](BF4)2.2MeOH (1) [TPA = tris(2-pyridylmethyl)amine] and [(TPA)CoII(CA*3-)CoII(TPA)](BF4).2Et2O (2) with a bridging chloranilate radical ligand formed by reduction of 1 are crystallographically and magnetically characterized. 1 has shown a weak antiferromagnetic coupling within the Co(II) dimer [J/kB = -0.65 K (-0.45 cm(-1))], while 2 has a 2 orders of magnitude stronger antiferromagnetic interaction between the Co(II) ion and a radical [J/kB = -75 K (52 cm(-1))].
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