Temperature-dependent dimerization of TCNQ anion-radical in [Ni(bpy)3]2(TCNQ–TCNQ)(TCNQ)2·6H2O: Single-crystal structure, magnetic and quantum chemical study

An Old Crystallization Technique as a Fast, Facile, and Adaptable Method for Obtaining Single Crystals of Unstable “Li2TCNQF4” and New Compounds of TCNQ or TCNQF4: Syntheses, Crystal Structures, and Magnetic Properties

“…Within our broader interest in the crystal structures and magnetic properties of heterospin Ni­(II) complexes with the TCNQ AR, , we have prepared a novel heterospin complex [Ni­(2 ampy ) 2 (TCNQ) 2 ] ( 1 ; 2 ampy = 2-aminomethyl-pyridine) with two TCNQ ARs coordinated to the Ni­(II) central atom. This compound has been prepared in two different ways, as microcrystals from a methanol solution of NiCl 2 ·6H 2 O and 2 ampy with LiTCNQ and as single crystals of sufficient quality for X-ray structure determination from the reaction in methanol of crystals of an insoluble 2 ampy coordination compound, [Ni­(2 ampy ) 2 (NO 3 ) 2 ], with soluble LiTCNQ, in a fast, facile procedure designed to avoid decomposition.…”

“…TCNQ in the form of the AR is interesting from a magnetic point of view since the presence of an unpaired electron makes it magnetically active ( S = 1/2). The magnetic properties of numerous compounds based on the TCNQ AR have been studied in detail. − Besides magnetic properties, TCNQ-containing compounds were studied as promising semiconducting materials, , materials for quantum computing, electric capacitors, and gas sensors, and as porous materials for gas storage and separation …”