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Capítulo IPEN-doc 23973 Fluoride bulk crystals growth2016 - BALDOCHI, S.L.; MORATO, S.P.Fluoride crystals have long presented a challenge for chemists and physicists, because their preparation often requires very specific procedures. Their synthesis usually requires the use of toxic and/or corrosive materials, procedures demanding suitable equipment, and safety operational norms. Additionally, most of the fluoride compounds are moisture sensitive. As a result, a dry working environment is needed. In spite of this, fluoride crystals have found many applications as dosimeters, information storage devices, X-ray monochromators, and, in particular, in the field of optics as laser hosts and other components such as windows, which has encouraged the development of research work on the preparation of large crystals. The successful preparation of bulk fluoride crystals is dependent upon a number of factors directly related to the crystal growth conditions of the most important is the purity of the raw material. The choice of high purity commercial salts will not always assure the growth of a crystal with high quality. First, the manipulation of fluorides without the correct procedures can easily introduce moisture contamination. Fluorides are very sensitive to water and oxygen, which are always present in the work environment. Second, commercial fluorides are rarely of sufficient purity, with respect to oxygen contaminants. Usually, starting materials are ‘five-nines’ (99.999%) pure with respect to the cation. Oxygen-related impurities, such as OH , COH , NO2 , present vibrational modes in the infrared range. Their presence, even in small concentrations, can be detrimental to the quality of infrared optical devices. In general, most simple fluoride crystals, such as alkali halides (LiF, NaF, RbF) or alkaline-earth fluorides (CaF2, SrF2, BaF2), are grown directly from commercial chemicals, after a preliminary treatment to eliminate moisture and oxygen contaminants. However, more complex fluoride compounds (e.g., LiSrAlF6 or BaY2F8) need to be carefully synthesized before the growth process. A preliminary treatment or synthesis of the raw material to be used for the crystal preparation is the first step in the growth of fluoride crystals.Artigo IPEN-doc 06639 Laser cleaning and texturizing on high-speed steel tools for enhanced PVD process2003 - LIMA, M.S.F.; VIEIRA JUNIOR, N.D.; MORATO, S.P.Resumo IPEN-doc 08369 Laser operation of Ndsub(x):Ysub(y)Gdsub(1-x-y)LiFsub(4) mixed crystals2003 - WETTER, NIKLAUS U.; MATOS, PAULO S.F. de; RANIERI, IZILDA M.; BALDOCHI, SONIA L.; VIEIRA JUNIOR, NILSON D.; MORATO, SPERO P.; COURROL, LILIA C.Publicação IPEN-doc 01508 Dosimetric properties of Lisub(2)Bsub(4)Osub(7):Tm pellets1987 - RZYSKI, B.M.; MORATO, S.P.Publicação IPEN-doc 01510 The thermoluminescent properties of Lisub(2)Bsub(4)Osub(7):Tm1987 - RZYSKI, B.M.; MORATO, S.P.Publicação IPEN-doc 01509 Luminescence studies of thulium doped Lisub(2)Bsub(4)Osub(7) glass and its applications1987 - RZYSKI, B.M.; MORATO, S.P.Publicação IPEN-doc 02449 Tecnologia de filmes finos1986 - VIEIRA JUNIOR, N.D.; AMBROSIO, E.; MORATO, S.P.Publicação IPEN-doc 00839 A review on the photochemistry of OHsup(-) and Hsup(-) defects in KCl crystals1978 - MORATO, S.P.; LUTY, F.Publicação IPEN-doc 00498 Photochemistry and reactions of OHsup(-) defects and F centers in alkali halides1978 - MORATO, S.P.; LUTY, F.Publicação IPEN-doc 00592 A new fundamental hydrogen defect in alkali halides1978 - MORATO, S.P.; LUTY, F.