Joshaghani M, Gholivand MB, Ahmadi F. Spectrophotometric and conductometric study of complexation of salophen and some transition metal ions in nonaqueous polar solvents.
SPECTROCHIMICA ACTA. PART A, MOLECULAR AND BIOMOLECULAR SPECTROSCOPY 2008;
70:1073-1078. [PMID:
18343186 DOI:
10.1016/j.saa.2007.10.015]
[Citation(s) in RCA: 21] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2007] [Revised: 09/30/2007] [Accepted: 10/15/2007] [Indexed: 05/26/2023]
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.
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