title: Spectrophotometric and conductometric study of complexation of salophen and some transition metal ions in nonaqueous polar solvents.
abstract: The complexation reaction between Cu2+, Co2+ and Ni2+ metal cations with N,N'-bis(salicylidene)-1,2-phenylenediamine (salophen), in three nonaqueous polar solvents such as: acetonitrile (AN), dimethyl sulfoxide (DMSO), methanol (MeOH) and two binary mixtures of AN:DMSO and AN:MeOH at 25 degrees C were studied by spectrophotometric and conductometric methods. All investigated metal ions form 1:1 ML complex which their stability constants were determined and increase as Irving-Williams stability order of Co2+ < Ni2+ < Cu2+ in all solvent systems except in the pure MeOH and binary mixture of AN:MeOH 20:80; in which, Ni2+ < Co2+ < Cu2+ was observed. The values of the thermodynamic parameters (DeltaH degrees , DeltaS degrees and DeltaG degrees ) for complexation reactions obtained from the temperature dependence of the stability constants and the results show that for all metal ion complexes, the value of DeltaH degrees , DeltaS degrees and DeltaG degrees are solvent dependent.
authors.affiliation: Department of Chemistry, Faculty of Science, Razi University, Kermanshah 67149, Iran. MJoshaghani@razi.ac.ir
authors.forename: Mohammad
authors.initials: M
authors.lastname: Joshaghani
authors.forename: Mohammad B
authors.initials: MB
authors.lastname: Gholivand
authors.forename: Farhad
authors.initials: F
authors.lastname: Ahmadi
mesh_terms: D004553:Electric Conductivity; D007477:Ions / Q000737:chemistry; D015394:Molecular Structure; D012459:Salicylates / Q000737:chemistry*; D012997:Solvents / Q000737:chemistry*; D013053:Spectrophotometry; D013816:Thermodynamics; D028561:Transition Elements / Q000737:chemistry*
chemical_list: D007477:Ions; D012459:Salicylates; D012997:Solvents; D028561:Transition Elements; C090416:salophen