1448016-97-4Relevant academic research and scientific papers
Subtlety of the spin-crossover phenomenon observed with dipyridylamino-substituted triazine ligands
Wannarit, Nanthawat,Roubeau, Olivier,Youngme, Sujittra,Gamez, Patrick
, p. 730 - 737 (2013/05/22)
Reactions of the new, closely related ligands 4,6-dichloro- N,N-di(pyridine-2-yl)-1,3,5-triazine-amine (Cldpat) and 6- chloro-N'-phenyl-N,N- di(pyridin-2-yl)-1,3,5-triazine-2,4-diamine (Cladpat) with iron(II) thiocyanate produced coordination compounds with drastically distinct magnetic properties. The compound trans-[Fe(Cldpat)2(NCS)2](H2O) (1) is a highspin complex from room temperature down to 5 K whereas the analogous compound trans-[Fe(Cladpat) 2 (NCS) 2] (2) exhibits spin-crossover (SCO) properties with T1/2 = 178K. Compounds 1 and 2 (both in its low-spin and high-spin states) have been structurally characterized by X-ray diffraction studies, which revealed identical metal coordination spheres. The SCO properties of 2 have been thoroughly investigated by temperature-dependent magnetic susceptibility measurements and differential scanning calorimetry (DSC), and a LIESST process with rapid relaxation of the trapped HS species has been observed. The equivalent coordination compound with selenocyanate anions, namely [Fe(Cladpat) 2 (NCSe) 2] (3) also displays SCO properties, although more gradual and with a lower T 1/2 value of 166 K.
