Coordination number 8 fluorides geometries

Chromium (II) also forms sulfides and oxides. Chromium (II) oxide [12018-00-7], CrO, has two forms a black pyrophoric powder produced from the action of nitric acid on chromium amalgam, and a hexagonal brown-red crystal made from reduction of Cr202 by hydrogen ia molten sodium fluoride (32). Chromium (II) sulfide [12018-06-3], CrS, can be prepared upon heating equimolar quantities of pure Cr metal and pure S ia a small, evacuated, sealed quartz tube at 1000°C for at least 24 hours. The reaction is not quantitative (33). The sulfide has a coordination number of six and displays a distorted octahedral geometry (34). 

Geometry of the Fluorides, Chlorides, and Hydrides with LLP Coordination Number Up to Four... 

AB2 structures. Fluorides and oxides of the formula AB2, which are distinctly ionic, crystallize in structures determined by size considerations. As in the case of AB structures, it is the coordination geometry of anions around the cation that determines the structural arrangement. The coordination may be 8-, 6-, or 4-fold, fixing the corresponding anion coordination numbers to 4,3 or 2. We thus have the following structures for ionic AB2 compounds fluorite (8 4), rutile (6 3) and silica (4 2) and these structures are shown in Fig. 1.7. 

Iridium(V) complexes, 1158 fluorides, 1158 Iridium(VI) complexes, 1158 Iron complexes acetonitrile, 1210 analysis, 1180, biological systems, 1180 coordination geometries, 1183 coordination numbers, 1182-1187 dinitrosyldicarbonyl, 1188 Mdssbauer spectroscopy, 1181 nitric oxide, 1187-1195 nitrosyls binary, 1188 bis(dithiolene), 1193 carbonyl, 1188 dithiocarbamates, 1192 halides, 1193 iodide, 1193... 

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