Study of the 1 A1⇔5 T2 spin transition in mix-ligand complexes of iron(II) hexafluorosilicate with 1,2,4-triazole and 4-amino-1,2,4-triazole.

Synthesis procedures for mix-ligand complexes with a composition of Fe(Htrz)_{3(1- x)}(NH₂trz)_{3 x}SiF₆ · mH₂O, 0 ≤ x ≤ 1, m=1,2 are developed. Solid phases are isolated from water-ethanol solutions and studied by X-ray phase analysis, the method of static magnetic susceptibility (temperature range of 100 K to 400 K), IR and Mössbauer spectroscopy (at 200 K and 298 K). The temperatures of direct and inverse transitions are shown to depend on the complex composition. [ABSTRACT FROM AUTHOR]