INFLUENCE OF HIGH-PRESSURE ON EMISSION-SPECTRA AND CRYSTAL-FIELD STRENGTH FOR EU3+ IN GDOBR

The emission spectra of the EU3+ ion in GdOBr:Eu3+ were measured in th e range of pressure from 0 GPa to 12.4 GPa. The energy level schemes e stablished from the spectra show that the splittings of the F-7(1), F- 7(3) and D-5(1) multiplets decrease obviously with increasing pressure . The crystal-field parameters B-q(k) and the crystal-field strength p arameter S versus B-q(k) were determined at different pressures. With pressurization S reduces and the J-mixings of the state functions for the EU3+ ion decrease, which is in agreement with the decrease of the multiplet-splittings. This shows that for EU3+ in REOX:Eu3+ the diminu tion of the crystal-field strength with pressure, the authenticity of which is under suspicion for several years, is certain.