Synthesis and characterization of yttrium and lanthanide perchlorate complexes of 4-salicylideneamino-3-mercapto-6-methyl-1,2,4-triazin (4H)-5-one

A few complexes of La (III), Ce (III), Pr (III), Nd (III), Sm (III), Eu (II I), Gd (III), Tb(III), Dy (III) and Y (III) perchlorates with 4-salicyliden eamino-3-mercapto-6-methyl-1,2,4-triazine (4H)-5-one (SMMT) have been isola ted and characterised by analytical, magnetic, molar conductance, thermal a nd infrared spectral studies and it is found that the ligand molecule coord inate to the metal ions.through the carbonyl oxygen, phenolic oxygen and th e azomethine nitrogen atoms. The complexes formed are neutral in nature whi ch suggests that the perchlorate ion is bonded to the metal ion unidentatel y. The complexes are formulated as [Ln (SMMT)(2)ClO4] with a coordination n umber of seven for the lanthanide ions (where Ln=La, Ce, Pr, Nd, Sm, Eu, Gd , Tb, Dy and Y). All these complexes are thermally stable upto about 120 de grees C.