Chromium arsenides

In Moroccan deposits, cobalt occurs with nickel in the forms of smaltite, skuttemdite, and safflorite. In Canadian deposits, cobalt occurs with silver and bismuth. Smaltite, cobaltite, erythrite, safflorite, linnaeite, and skuttemdite have been identified as occurring in these deposits. AustraUan deposits are associated with nickel, copper, manganese, silver, bismuth, chromium, and tungsten. In these reserves, cobalt occurs as sulfides, arsenides, and oxides. 

Chromium Sesqui-arsenide, CrgASg, is prepared by heating finely divided chromium with excess of arsenic at 700° C. in a sealed exhausted tube, the product being powdered and again heated. The... 

Monolayers can be transferred onto many different substrates. Most LB depositions have been performed onto hydrophilic substrates, where monolayers are transferred when pulling the substrate out from the subphase. Transparent hydrophilic substrates such as glass [18,19] or quartz [20] allow spectra to be recorded in transmission mode. Examples of other hydrophilic substrates are aluminium [21,22,21 and 24], chromium [9,21] or tin [26], all in their oxidized state. The substrate most often used today is silicon wafer. Gold does not establish an oxide layer and is therefore used chiefly for reflection studies. Also used are silver [27], gallium arsenide [27,28] or cadmimn telluride wafer [28] following special treatment. 

H. Moissan found that arsenic reacts with chromium trioxide with incandescence, forming arsenide. According to C. Reichard, an aq. soln. of chromium trioxide is reduced by arsenic trioxide and the reaction was studied by R. E. de Lury, and W. L. Miller. A. Skrabal showed that if the reaction proceeds slowly, violet chromic salt is formed, and if rapidly, a green salt—vide 9. 51, 22, for the arsenic chromates formed by condensation with arsenic acid. 

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