Optical spectroscopy and magnetic studies of dimeric europium capronate with 1,10-phenanthroline

Luminescence, excitation of luminescence and absorption spectra of europium capronate crystals as well as vibrational IR and Raman spectra at 4.2, 77 and 293 K were obtained. Magnetic susceptibility measurements were carried out down to 1.7 K. Correlations between the spectral and magnetic propertie s and details of the structure of the title compound were studied. The crys tal field parameters were calculated using the Stark splitting of the Eu3electronic levels. The oscillator strengths were evaluated. Changes in the spectra and magnetic susceptibility of Eu(C5H11COO)(3)Phen with increasing temperature from 4.2 to 293 K proves transformation of the crystal lattice. The subtle splitting of bands in the regions of the D-5(0)-->F-7(1) and D- 5(0)-->F-7(2) transitions was revealed. Several possible causes of this phe nomenon, including resonant vibronic interactions and/or the possible effec t of ion-pair interactions, are discussed.