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In this work, we investigated the structural and the optical properties of AuCl semiconductor nanocrystals embedded in KCl single crystals. The AuCl nanocrystals were obtained by doping the KCl crystalline matrix with gold using the Czochralski method. The X-ray diffraction showed the formation of the AuCl nanocrystals in KCl with a tetragonal structure. The average radius of the AuCl nanocrystals is estimated using the Scherrer formula. The photoluminescence spectra presented a band emission situated at 580 nm leading to the formation of the AuCl nanocrystals within KCl.

Single crystals of KBr containing the (O2‐ ‐ F+) color centres and elaborated in atmospheric air by the Czochralski method are studied. The measure of the UV‐visible emission spectra at 78 K present several emission bands situated between 340 and 800 nm. The photoluminescence excitation shows that these emissions are attributed to O‐2 and (O2‐ ‐ F+) centres. This study show the new emission bands of (O2‐ ‐ F+) centres which are situated in the UV‐visible spectral domain. The comparison between the emission spectra before and after the thermal treatment of samples shows clearly the transformation of O‐2 centers at high temperature to (O2‐ ‐ F+) centres. (© 2007 WILEY‐VCH Verlag GmbH & Co. KGaA, Weinheim)

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