Bismuth halide sulfide

The compounds have been prepared by annealing stoichiometric amounts of the elements or the respective antimony(III) or bismuth(III) sulfide and halides in sealed silica ampuls.11 12 Good crystals are obtained by using a surplus of M2X3.12 The conditions for the preparation of these thiohalides are given in Table VI. 

Bismuth sulfide (Bi2S3) is a dark brown to grayish black solid, readily obtained by heating bismuth with sulfur or by adding an alkali sulfide to the aqueous solution of bismuth(III) salts. It is used as a high temperature lubricant. The sulfide is almost insoluble in water, but dissolves in concentrated nitric acid and hot hydrochloric acid. Concentrated aqueous potassium sulfide dissolves bismuth sulfide to form bismuth thiobismuthate KBi 2, which is readily oxidized in air. Fusion of the sulfide with bismuth halide (BiXa) gives the corresponding halosulfide (BiXS) as an air-stable solid. Bismuth sulfide of 99% purity costs US 153.30 ( 37 9(X)) per 250 g. 

Alkaline-Earth Sulfides and Sulfoselenides. Activated alkaline-earth sulfides have been known for a long time their luminesence is very varied. Emission bands between the ultraviolet and near infrared can be obtained by varying the activation. They are produced by precipitation of sulfates or selenites from purified solutions, followed by reduction with Ar-H2. The addition of activators, for example, copper nitrate, manganese sulfate, or bismuth nitrate, is followed by firing for 1 - 2 h. Alkaline-earth halides or alkali-metal sulfates are sometimes added as fluxes. 

Class I. ELEMENTS. A. Metals. Cubic copper, silver, gold, iron, platinum, iridium. - Tetragonal tin. - Rhombohedral and Hexagonal arsenic, antimony, bismuth, tellurium, (Os, Ir). - B. Metalloids. Cubic diamond. - Hexagonal graphite. - Orthorhombic sulfur, iodine. - Monoclinic sulfur, selenium. - Class II. SULFIDES. - Class HI. HALIDES. -Class IV. OXIDES, divided into SIMPLE OXIDES and COMPLEX OXIDES, such as CARBONATES, PHOSPHATES, SILICATES, BORATES and SULFATES. 

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