Silver compounds high temperature

The thermodynamic behaviour of silver and solubilities of silver and its compounds have been computed in an electrochemical study of silver in potassium hydroxide solutions at high temperature ". ... 

Some ionic solids have been discovered that have a much higher conductivity than is typical for such compounds and these are known as fast-ion conductors. One of the earliest to be noticed, in 1913 by Tubandt and Lorenz, was a high temperature phase of silver iodide. 

Agl, in its low temperature form, crystallizes in the (hep) wurtzite structure. The silver ions occupy tetrahedrally coordinated sites. The fast ion conducting Agl (7 >420K) is bcc. One can stabilize structural disorder at low temperature not only by incorporating cations such as Rb+, NH, etc., but also by adding S2 to reconstruct the anion sublattice and obtain Ag3SI. This compound exists in three different structures. At high temperature (>519K), it is bcc and both the cations and... 

Heterogeneous oxidative processes operate at high temperatures (250-450 6C) and are useful for the synthesis of acrolein and acrylic acid from propylene over bismuth molybdate catalysts, the synthesis of maleic and phthalic anhydrides from the oxidation of benzene (or C4 compounds) and naphthalene (or o-xylene) respectively over vanadium oxide,101 arid the synthesis of ethylene oxide from ethylene over silver catalysts.102... 

Physical and Chemical Properties. No data exist on the partition coefficients and Henry s law constant for silver and its compounds. A vapor pressure has been determined for silver at very high temperatures (greater than 900 °C), but not for any of its compounds. Generally, the fate of silver in the environment is fairly well understood however, a determination of these environmentally... 

The majority of unipolar ionic conductors identified to date are polymorphic compounds with several phase transitions, where the phases have different ionic conductivities owing to modifications in the substructure of the mobile ions [28], One of the first studied cationic conductors was a-Agl [21]. Silver iodide exhibits different polymorphic structures. Agl has a low-temperature phase, that is, [3-Agl, which crystallizes in the hexagonal wurtzite structure type, and a high-temperature cubic phase, a-Agl, which shows a cubic CsCl structure type [20,22] (see Section 2.4.5). 

Alpha silver iodide, the high-temperature phase of Agl, shows an extraordinarily high Ag+ ionic conductivity. On the other hand, the conductivity at room temperature, that is, the conductivity of P-AgI is considerably lower [12,20], In the a-Agl phase, there are only two Ag+ ions distributed over the octahedral and tetrahedral positions of the cubic lattice, producing many vacancies that are accessible for Ag+ ions to bypass through the structure [20], Then, in order to operate these materials it is necessary to stabilize the high-temperature a phase at low temperatures [12], Subsequently, a considerable amount of studies of ternary and quaternary compounds have been performed with the purpose of stabilizing fast ionic phases at low temperatures [29],... 

It is noteworthy that the corresponding silver compounds do not exist in this structure. AgLuS2 (468), which we expect to be non-metallic, crystallizes in a disordered NaCl structure (high-temperature modification ). The structure of AgYS2, on the other hand, is a monoclinic, strongly distorted but ordered version of the rocksalt type (468). 

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