METHOD FOR PRODUCING EUROPIUM (II) EUF2 DIFLUORIDE CRYSTALS

摘要

FIELD: chemistry.;SUBSTANCE: method for producing europium (II) EuF₂ difluoride crystals is carried out in two stages, at the first of which EuF₃ is pre-melted and its melt is fluorinated to remove the impurity of oxygen, after cooling the melt, the fluorinated EuF₃ is milled and mixed with the pre-prepared crystalline silicon powder (Si) to produce the batch of the desired composition in accordance with the equation 4EuF₃+Si=4EuF₂+SiF₄↑. At the second stage, the produced batch is melted, homogenized and the batch melt is crystallised by directional crystallisation using a fluorine-containing atmosphere, producing single-crystal europium EuF₂ difluoride boules. As a directional crystallisation method, for example, the Bridgman-Stockbarger method is used. The fluorine-containing atmosphere in the crystallisation process is created by the decomposition of ammonium hydrofluorides or alkaline-earth elements. At the first step, the silicon powder can be introduced directly into the EuF₃ melt with the aid of a dispenser ensuring compliance with a predetermined relationship between EuF₃ and silicon.;EFFECT: increasing the yield.;4 cl, 3 dwg, 1 ex