Bis(15-crown-5)-1,4-distyrylbenzene and its complexes with metal perchlorates: photonics and structure

Resumo

Photoprocesses of bis(15-crown-5)-1,4-distyrylbenzene (DSB) and its complexes with barium and lead perchlorates in MeCN were studied by absorption, luminescence, and laser kinetic spectroscopies. Triplet DSB complexes are involved in the degradation of electronic excitation energy along with the trans—cis-isomerization and fluorescence processes. The most effective intersystem crossing was observed for the complex with lead perchlorate. The process is accompanied by a decrease in the quantum yield of DSB fluorescence and no trans—cis-isomerization is observed in this case. Shifts of spectral bands observed in the absorption and fluorescence spectra and the changes in the band intensities as well as the ability of DSB to form the 2: 2 bisandwich complex with barium perchlorate were explained using the results of quantum chemical calculations.