Rubidium silver iodide
Encyclopedia
Rubidium silver iodide is a ternary
inorganic compound
with the formula RbAg4I5. It is an unusual solid where the electrical conductivity involves movement of silver
ion
s within the crystal lattice. It was discovered while searching for chemicals which had the ionic conductivity
properties of alpha-phase silver iodide
at temperatures below the 146 °C for AgI.
Rubidium silver iodide can be formed by melting together or grinding together stoichiometric quantities of rubidium iodide
and silver(I) iodide. The reported conductivity is 25 siemens
per metre (that is a 1×1×10 mm bar would have a resistance of 400 ohms along the long axis).
The crystal structure is composed of sets of iodine tetrahedra; they share faces through which the silver ions are able to diffuse.
Rubidium silver iodide was proposed around 1970 as a solid electrolyte for batteries, and has been used in conjunction with electrodes of silver and of RbI3
.
Rubidium silver iodide family is a group of compounds and solid solutions which are isostructural with the RbAg4I5 alpha modification. The examples of such advanced superionic conductors with mobile Ag+ and Cu+ cations are: KAg4I5, NH4Ag4I5, K1−xCsxAg4I5, Rb1−xCsxAg4I5, CsAg4Br1−xI2+x, CsAg4ClBr2I2, CsAg4Cl3I2, RbCu4Cl3I2, KCu4I5 and others.
Ternary compound
In chemistry, a ternary compound is a compound containing three different elements. An example of this is sodium phosphate, Na3PO4. The sodium ion has a charge of 1+ and the phosphate ion has a charge of 3-. Therefore, three sodium ions are needed to balance the charge of one phosphate ion. Another...
inorganic compound
Inorganic compound
Inorganic compounds have traditionally been considered to be of inanimate, non-biological origin. In contrast, organic compounds have an explicit biological origin. However, over the past century, the classification of inorganic vs organic compounds has become less important to scientists,...
with the formula RbAg4I5. It is an unusual solid where the electrical conductivity involves movement of silver
Silver
Silver is a metallic chemical element with the chemical symbol Ag and atomic number 47. A soft, white, lustrous transition metal, it has the highest electrical conductivity of any element and the highest thermal conductivity of any metal...
ion
Ion
An ion is an atom or molecule in which the total number of electrons is not equal to the total number of protons, giving it a net positive or negative electrical charge. The name was given by physicist Michael Faraday for the substances that allow a current to pass between electrodes in a...
s within the crystal lattice. It was discovered while searching for chemicals which had the ionic conductivity
Ionic conductivity
Ionic conduction is the movement of an ion from one site to another through defects in the crystal lattice of a solid. Ionic conduction is one aspect of current....
properties of alpha-phase silver iodide
Silver iodide
Silver iodide is a yellow, inorganic, photosensitive iodide of silver used in photography, in medicine as an antiseptic, and in rainmaking for cloud seeding.-Crystal structure:...
at temperatures below the 146 °C for AgI.
Rubidium silver iodide can be formed by melting together or grinding together stoichiometric quantities of rubidium iodide
Rubidium iodide
Rubidium iodide is a compound with a melting point of 642 °C. Its chemical formula is RbI....
and silver(I) iodide. The reported conductivity is 25 siemens
Siemens (unit)
The siemens is the SI derived unit of electric conductance and electric admittance. Conductance and admittance are the reciprocals of resistance and impedance respectively, hence one siemens is equal to the reciprocal of one ohm, and is sometimes referred to as the mho. In English, the term...
per metre (that is a 1×1×10 mm bar would have a resistance of 400 ohms along the long axis).
The crystal structure is composed of sets of iodine tetrahedra; they share faces through which the silver ions are able to diffuse.
Rubidium silver iodide was proposed around 1970 as a solid electrolyte for batteries, and has been used in conjunction with electrodes of silver and of RbI3
Triiodide
In chemistry, triiodide can have several meanings. Triiodide primarily refers to the triiodide ion, I3−, a polyatomic anion composed of three iodine atoms. For some chemical compounds, triiodide indicates a salt of the named cation with the triiodide anion. Examples include sodium triiodide, ...
.
Rubidium silver iodide family is a group of compounds and solid solutions which are isostructural with the RbAg4I5 alpha modification. The examples of such advanced superionic conductors with mobile Ag+ and Cu+ cations are: KAg4I5, NH4Ag4I5, K1−xCsxAg4I5, Rb1−xCsxAg4I5, CsAg4Br1−xI2+x, CsAg4ClBr2I2, CsAg4Cl3I2, RbCu4Cl3I2, KCu4I5 and others.