Intra-zoned luminescence in alkali earth metal carbonates

Full text: The fundamental plasma luminescence of wide band alkali halide crystals has been found out by Vaisburd et al. This broadband luminescence with very short duration of attenuation (∼10-12 s) arises at an irradiations of crystals with electronic beam powerful pulses of nanosecond duration. It is related to radiating 'hot' electrons and holes in a conductivity zone and in a valent zone, accordingly and in later time began to refer to as an intra-zoned luminescence. The data set on revealing features of display of an intra-zoned luminescence in different classes of crystals now proceeds. We investigated a fast luminescence at excitation with pulse electrons (3 nanoseconds) in crystals CaCO3, SrCO3, BaCO3 and MgCO3. In spectra all investigated carbonates it is possible to allocate two areas: area concerning high intensity of a fast luminescence (from 2 eV down 3 eV) and area of low intensity (is higher 4 eV) with slow recession at increase in photon energy. Thus it is typical, that in area concerning high intensity at rise in temperature from 80 up to 300 K a sample intensity of luminescence falls down, whereas in area is higher 5 eV with rise in temperature of a sample increase of intensity is observed. This broadband fast (is shorter than the time sanction of the equipment) should be connected a luminescence poorly dependent on temperature and a modular status of a sample with intra zoned transitions This luminescence reaches from 2 eV down to 7 eV but as for carbonates while is absent the reliable data on structure of a valent zone, division of an intra-zoned luminescence into electronic and hole components is not obviously possible on the basis of spectra of a fast luminescence. The nature of other luminescence processes arising at excitation with pulse electrons is discussed