  In the present paper we report on the combined experimental and theoretical
study of the Sr6-xEuxBP5O20 (x=0.01; 0.03; 0.05; 0.07; 0.09; 0.11; 0.13; 0.15)
phosphors. Details of the samples preparation and spectroscopic measurements
are followed by the analysis of the room-temperature absorption and emission
spectra, which yielded the main parameters of the electron-phonon coupling,
such as Huang-Rhys factor, Stokes shift, effective phonon energy, and
zero-phonon line position were determined for the first time for the studied
system. The obtained parameters were used to model the emission band shapes,
which perfectly reproduce the experimental results for all samples.
