Polycrystalline samples of the new semimagnetic semiconductor (x = 0.06, 0.12, 0.25, 0.39, 1.00, 1.40, 1.80) were obtained by ceramic technology. An x-ray diffraction experiment was performed on all of the samples at room temperature. These data provided the basis for Rietveld refinements. The refinements showed that ions preferentially occupy the 24d position. The lattice constants and the mean cation - anion distances decrease linearly with the -ion concentration. The inverse magnetic susceptibilities for all of the samples depend linearly on the temperature for . In this region only the lowest Kramer's doublet is populated, and for that level the effective magnetic quantum number is deduced. The Curie - Weiss paramagnetic temperatures obtained from the low-temperature region depend linearly on the concentration x. Over the whole experimental region , the magnetic susceptibility deviates from the Curie - Weiss law, and its calculation requires inclusion of the first excited Kramer's doublet. The effective magnetic quantum number and energy gap of the first excited doublet were deduced.

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A modification of Stober's apparatus is presented for growing crystals in a laboratory chamber furnace. In addition to simplicity, the proposed apparatus has the following advantages: (a) absence of mechanical shocks; (b) spontaneous change and self-adjusting to most convenient crystallisation rate of the substance; (c) possibility of growing crystals in vacuum or an inert atmosphere. A formula for the crystallisation rate has been derived and analysed.

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