Influence of π stacking on the magnetic properties of the copper(II) complex with 6-phenyl-3-(2-pyridyl)-5-trifluoroacetylmethylidene-4,5-dihydro-1,2,4-triazine

The new N,N,O -ligand 6-phenyl-3-(2-pyridyl)-5-(trifluoroacetylmethylidene)-4,5-dihydro-1,2,4-triazine (L) was synthesized, and its complex with Cu II was prepared. The structure of the complex was established by X-ray diffraction. Magnetic measurements and ESR studies were carried out. Ab initio calculations of the electronic structure, exchange interactions, and the effective magnetic moment were performed. The intrastack polarization effect between the π states of 1,2,4-triazine and the d states of copper was revealed and numerically validated.