Thermal properties of [Co(en) sub(2)Cl sub(2)]Cl in solid state. Cis-trans isomerization of the [Co(en) sub(2)Cl sub(2)] super(+) complex ion in methanol

• Published in: Reaction kinetics, mechanisms and catalysis Vol. 113; no. 2; pp. 321 - 331
• Main Authors: Jacewicz, Dagmara, Pranczk, Joanna, Wyrzykowski, Dariusz, Zamojc, Krzysztof, Chmurzynski, Lech
• Format: Journal Article
• Language: English
• Published: 01.12.2014
• Subjects: Glint; Isomerization; Isomers; Methyl alcohol; Rate constants; Reaction kinetics; Thermal properties; Thermal transformations
• ISSN: 1878-5190; 1878-5204
• DOI: 10.1007/s11144-014-0742-y

Thermal decompositions of the trans-[Co(en) sub(2)Cl sub(2)]Cl and cis-[Co(en) sub(2)Cl sub(2)]Cl complex isomers have been studied using the TG-FTIR and TG-DSC-MS techniques. The measurements were carried out in argon atmosphere over the temperature range 293-873 K. The influence of the configurational geometry on the pathways of thermal transformations was discussed. Furthermore, kinetic studies on the reaction of the cis-trans isomerization of the [Co(en) sub(2)Cl sub(2)]Cl complex salt in methanolic solutions were performed using UV-Vis spectrophotometry at five temperatures in the 293-313 K temperature range. The observed rate constants were computed using the "Glint" program based on the global analysis. It has been found that the cis-trans isomerization of [Co(en) sub(2)Cl sub(2)]Cl is a first order reaction. Furthermore, the cis/trans [Co(en) sub(2)Cl sub(2)]Cl isomerization proceeds according to the dissociative mechanism.