Two dicopper(Ⅱ) complexes, [Cu2(H2L)(μ-N3)](ClO4)2.1/2C2H5OH(1) and [Cu2(HL)(μ-N3)(ClO4)(C2H5OH)(H2O)](2), have been synthesized and characterized, where H3L is the binucleating ligand 2, 6-diformyl-4- methylphenol di(benzoylhydrazone). The crystal structure of 2 has been determined. Crystal data for 2 are monoclinic, space group P21/c, a=1.0967(4)nm, b=0.7684(2)nm, c=3.5724(7)nm, β=90.08(2)°, V=3.0103nm^3, Z=4, Dc=1.61g.cm^-^3, μ=15.66cm^-^1, F(000)=1488. The final R and Rw values are 0.083 and 0.088, respectively. The analysis of variable-temperature (4~300K) magnetic susceptibility data indicates that a medium antiferromagnetic interaction occured between copper(Ⅱ) ions. The exchange parameters (2J) are -86.8cm^-^1 for 1 and -132.4cm^-^1 for 2, respectively. The effect of tautomeric isomeride on magnetic interaction was discussed by molecular mechanics and CNDO/2 methods.

Key words: PHENOL P, INFRARED SPECTROPHOTOMETRY, ELEMENTAL ANALYSIS, CRYSTAL STRUCTURE, COPPER COMPLEX, TAUTOMERISM, MAGNETISM, MOLECULAR MECHANICS, BENZOYL HYDRAZINE