Characterization of Tetracyanopyridine (TCNPy)‐Based Magnets: V[TCNPy]₂⋅z (CH₂Cl₂) (T_c=111 K) and V[TCNPy]₃⋅z (CH₂Cl₂) (T_c=90 K)

Abstract

The reaction of 2,3,5,6-tetracyanopyridine (TCNPy) with V(CO)6 in CH2 Cl2 forms new organic-based magnets of V[TCNPy]x ⋅z (CH2 Cl2 ) (x=2, 3) composition. Analysis of the IR spectra suggests that the TCNPy is reduced and coordinated to V(II) sites through the nitriles. V[TCNPy]x order as ferrimagnets with 111 and 90 K Tc values for V[TCNPy]2 and V[TCNPy]3 , respectively. Their respective remanent magnetizations and coercive fields are 1260 and 250 emuOe mol(-1) and 9 and 6 Oe at 5 K, and they exhibit some spin-glass behavior.

Synthesis and Characterization of a Family of Molecule-Based Ferrimagnetic Network Solids Containing Fluoro-Substituted Dicyanostilbene Acceptors

“…Antiferromagnetic coupling of the three unpaired electrons on V and one unpaired electron on each bridging organic radical yields long-range magnetic order. V­[DCPFS] 2 · x (solvent) is an example of a broader class of compounds − that includes the first room-temperature molecule-based ferrimagnet, V­[TCNE] x · y (CH 2 Cl 2 ), where x ≈ 2 and TCNE = tetracyanoethylene (Figure b), reported by Manriquez et al a few years earlier, but differs in that it has only two nitrile functional groups on the bridging ligand/acceptor available to form the network. The TCNE compound remains of great interest for possible use in the spintronics field. , …”

Magnetic ordering in a vanadium-organic coordination polymer using a pyrrolo[2,3-d:5,4-d′]bis(thiazole)-based ligand

“…tetracyanoquinodimethane (TCNQ) IIa and its substituted analogues IIb–f, 15 and N ,7,7-tricyanoquinomethanimine III; 16 (3) polycyano-substituted aromatic one-ring systems IV, e.g. tetracyanobenzene (TCNB), 17 tetracyanopyridine, 18 tetracyanopyrazine. 19 The discovery of magnetically ordered vanadium–organic hybrid materials using α,α′-dicyanoperfluorostilbene Id 13 provided evidence that relatively large ligands can be used for construction of new hybrid materials; however, the majority of the previously examined ligands are small in size.…”