AUGER-FREE LUMINESCENCE IN MIXED-ALKALI HALIDES

A specific kind of core luminescence, called Auger-free luminescence ( AFL), has been studied in mixed CsF1-xClx system within the range x = 0-0.03 by using synchrotron radiation as a light source. A new lumines cence band is found to appear at 4.5 eV in addition to the AFL, of CsF . This band is ascribed to the radiative transition of electrons from the Cl-. 3p impurity level to the Cs+ 5p core band. A brief discussion is given on the spectral shape of the 4.5-eV band.