| abstract |
The invention relates to a method for producing a polycrystalline block halide of the formula ALnX, in which Ln means one or more rare earth metals, X means one or more halogen atoms selected from Cl, Br or I, and A means one or more alkali metals, such as K, Li, Na, Rb or Cs, e, which may be 0, is less than or equal to 3f, and f is greater than or equal to 1, having a low content of water and oxyhalide, which includes the stage of heating the mixture, which, on the one hand, has at least one connection with at least one Ln-X bond New and, on the other hand, a sufficient amount of NHX in order to obtain the desired oxyhalide content, said heating stage leading to a molten mass containing rare earth metal halide, where this heating stage is followed by a cooling stage, and at the heating stage after reaching 300 ° C the temperature does not drop below 200 ° C until the molten mass is obtained. The blocks thus obtained make it possible to grow very pure single crystals having remarkable scintillation properties. |