Journal of Thermal Analysis and Calorimetry

, Volume 52, Issue 1, pp 177–185 | Cite as

The cis-trans Isomerization of Azobenzene in the Molten State: A useful test reaction for the kinetic evaluation of DSC measurements

  • N. Eckardt
  • H. J. Flammersheim
  • H. K. Cammenga


Contrary to the situation in the field of temperature, heat and heat flow rate calibration, so far no generally accepted and easily practicable chemical reaction exists with regard to a kinetic evaluation. A possible reaction would be the well-known first-order cis-trans isomerization of subcooled liquid azobenzene. Surprisingly, the evaluation of measurements performed with a power compensated calorimeter yields activation parameters, which are dependent on the heating rate. The desmearing of the curves does not produce any improvements. However, constant activation parameters are obtained, if a small self-heating of the sample during the exothermic reaction is taken into account.

azobenzene DSC kinetics 


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Copyright information

© Kluwer Academic Publishers 1998

Authors and Affiliations

  • N. Eckardt
    • 1
  • H. J. Flammersheim
    • 1
  • H. K. Cammenga
    • 2
  1. 1.FSU JenaInst. Phys. Chem.JenaGermany
  2. 2.TU BraunschweigInst. Phys. u. Theoret. Chem.BraunschweigGermany

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