Calcium chalcogenides

Luo H, Greene RG, Ghandehari K et al (1994) Structural phase transformations and the equations of state of calcium chalcogenides at high pressure. Phys Rev 850 16232-16237 Zimmer H, Winzen H, Syassen K (1985) High-pressure phase transitions in CaTe and SrTe. Phys Rev 832 4066-4070... 

Lead-calcium-silver anodes, 74 777 Lead-calcium-tin alloys, 74 775-776 Lead carbonates, 74 794-795 Lead chalcogenides, 79 157 Lead chloride, 74 785 Lead chromate... 

From the divalent chalcogenides the trend continues as expected, through the cyclopentadienide, which has been shown to be ionic in the case of other rare earths, alkaline earths and even manganese (II), through the chloride, the hydroxide (which is a strong base comparable to calcium hydroxide), and finally to the highly ionic sulfate. 

Many ionic compounds of AX2 stoichiometry possess the CaF2 (fluorite), or Na20 (antifluorite) structures shown in Figure 3.15. Fluorite is similar to CsCl, but with every other eight coordinate cation removed. Each fluoride anion is tetrahedrally coordinated by calcium ions. This structure is adopted by several fluorides and oxides. In the antifluorite structure, the coordination numbers are the inverse. Most oxides and other chalcogenides of the alkali metals (e.g. Na2Se, K2Se) possess the antifluorite structure, but so do some more covalent compounds, such as the silicides of Mg, Ge, Sn, and Pb. 

The study of some systems such as chalcogenides of zinc, cadmium, mercury, thallium, bismuth, etc. (binary or multicomponent) can be achieved in "low temperature" cell. In this case the calcium chloride (CaCb) is dissolved in glycerol between 40 and 180°C. Calcium... 

The following chemical symbols are used in this chapter R designates the rare earth elements, including the lanthanides, yttrium and scandium M stands for the elements of group I (lithium, sodium, calcium, rubidium, cesium, copper, silver), X is used to designate chalcogenides (sulphur, selenium, tellurium). 

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