Shock wave study of ring opening processes in biphenylene

The thermal decomposition of biphenylene was studied by UV absorption spect roscopy in reflected shock waves over the temperature range 1470-1860 K. Ra tes for the first three steps of the reaction sequence were determined, the primary step being characterized by a rate constant of k = 1.2 x 10(16) ex p(-374 kJ mol(-1)/RT) s(-1). By comparison with single pulse shock tube mea surements the reaction mechanism could be identified as a sequence of ring opening processes followed by fragmentation of the forming linear chains.