Physicochemical Problems in the Preparation of Defect-free Monocrystals of Lanthanum Hexaboride

The physicochemical basis of the preparation of single crystals of stoichiometric lanthanum hexaboride (a promising new material for emission electronics) is discussed. It is shown that stoichiometric defect-free monocrystals can be prepared only by allowing for the form of the homogeneity region in the phase diagram of the crystalline compound. Studies of defects in the crystal structure are reviewed, and their results are shown to be related to the form of the homogeneity of lanthanum hexaboride. Some physicochemical properties and some possible applications of lanthanum hexaboride monocrystals are examined. The bibliography includes 150 references.