Photochemical Properties of Europium(III) Methylbenzoates

A study is performed of the spectral luminescence of complex compounds of europium(III) with o-methylbenzoic acid and nitrogen- and phosphorus-containing neutral ligands of o- and m-methylbenzoic acids. An analysis is made of the spectra of electronic absorption, luminescence excitation, and the Stark structure of D-5(0)-F-7(j) (j = 0-2) electronic transitions in the low-temperature luminescence spectra of complex mixed-ligand europium(III) o-methylbenzoates. It is established that the energy of excitation is transferred to the europium(III) ion from the levels o-methylbenzoic acid and nitrogen- and phosphorus-containing neutral ligands. A comparative analysis of luminescent parameters is performed for m- and o-europium(III)-methylbenzoates. It is shown that the luminescence of o-methylbenzoates of europium(III) is higher than that of m-europium(III)-methylbenzoates.