PHYSICOCHEMICAL STUDY OF SPIN CROSSOVER IN THE IRON(II) NAPHTHALENE-2-SULFONATE COMPLEX WITH 4-AMINO-1,2,4-TRIAZOLE

Physicochemical properties of the iron(II) 2-naphthalenesulfonate complex with 4-amino-1,2,4-triazole ([Fe(NH 2 trz) 3 ](ns) 2 ·2H 2 O ( I )) are studied. The complex exhibits the 1 A 1 ↔ 5 T 2 spin crossover. Complex I and the initial compound for its preparation, Fe(ns) 2 ( II ), are studied by static magnetic susceptibility, conductometry, spectrophotometry, and cyclic voltammetry methods. The μ eff ( T ) dependence for I shows that the spin transition is abrupt both in the initial complex and in the DMF solution. Forward and inverse spin crossover temperatures are determined.