Luminescence characterisation of the reaction system histidine-KBrO3-Tb(III)-H2SO4.

Chemiluminescence of the system containing Tb(III) ions, histidine and bromate ions in acid solution was studied. The kinetic curves and CL emission spectra of the system were discussed. The emission spectrum of the histidine-Tb(III)-KBrO3-H2SO4 system revealed two emission maxima at approximately 490 and 550 nm, characteristic of Tb(III) ions. Values of lifetimes of the Eu(III) excited states in Eu(III)-histidine system have shown that the histidine formed ML and ML2 complexes in neutral solution and did not make them in acidic environment. On the basis of the results, a possible mechanism of reaction system: histidine-Tb(III)-KBrO3-H2SO4 is presented.