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Ionic conduction (denoted by $λ$ ) 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.^[1] In solids, ions typically occupy fixed positions in the crystal lattice and do not move. However, ionic conduction can occur, especially as the temperature increases.^[2]

Ionic conduction is one of the mechanisms by which microwave ovens are believed to work. Microwaves cause ions dissolved in the microwaved sample to oscillate, colliding with neighboring molecules or atoms. These collisions cause agitation or motion, or heat. This mechanism is "important when considering the heating behavior of ionic liquids" within a microwave.^[3]

Ionic conduction in solids has been a subject of interest since the beginning of the 19th century. Michael Faraday established in 1839 that the laws of electrolysis are also obeyed in ionic solids like lead(II) fluoride (Template:Chemical formula) and silver sulfide (Template:Chemical formula).

Silver iodide

In 1921, Tubandt et al. found that silver iodide (Template:Chemical formula) has extraordinary high ionic conductivity. While measuring conductivity, they found that above 147 °C, AgI changes into a phase that has an ionic conductivity of ~ 1 –1 cm⁻¹, similar to that of its liquid phase. As a result, the high temperature phase of AgI was the first superionic conductor ever discovered. The highly conductive phase of AgI is now known as -AgI. It was shown that a sublattice cationic disorder takes place in -AgI. The liquid-like state of Ag⁺ ions, as proposed by Strock (1934, 1936) and later reinforced by others (Geller, 1977; Funke, 1976), consists of a cubic unit cell of iodide ions (I^-), in which a total of 42 sites (6 octahedral, 12 tetragonal and 24 trigonal bipyramidal) are available for 2 Ag⁺ ions, as shown in the Figure 1. O' Keeffe and Hyde (1976) have argued that this phase transition in AgI is dramatic and powerful, nothing less than the melting and have also shown that the entropy change at the superionic transition is comparable to its value at the melting. Thus, in the -phase, I⁻ ions form a body-centered cubic lattice and the Ag⁺ ions are distributed in such a way that 42 crystallographic equivalent interstices are available for the two Ag⁺ ions.

Alpha phase crystals of various materials like Template:Chemical formula, Template:Chemical formula, Template:Chemical formula, etc. were soon discovered (Tubandt, 1932). By the early 1930s, it was demonstrated that these fast ionically conducting solids could be treated entirely the same as aqueous electrolytes from the viewpoint of chemical reactions and thermodynamics, hence these materials were labeled solid electrolytes.

References

^ Richard Turton. (2000).The Physics of Solids. New York:: Oxford University Press. ISBN 0198503520.
^ www.teknik.uu.se/ftf/education/Disordered_materials/Ion_conduction.pdf
^ Kappe, C. O.; Stadler, A. Microwaves in Organic Synthesis and Medicinal Chemistry; Wiley-VCH: Weinheim, 2005. p. 12. ISBN 3527312102.

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[1] Richard Turton. (2000).The Physics of Solids. New York:: Oxford University Press. ISBN 0198503520.

[2] www.teknik.uu.se/ftf/education/Disordered_materials/Ion_conduction.pdf

[3] Kappe, C. O.; Stadler, A. Microwaves in Organic Synthesis and Medicinal Chemistry; Wiley-VCH: Weinheim, 2005. p. 12. ISBN 3527312102.

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+'''Ionic conduction''' (denoted by {{math|''&lambda;''}}) is the movement of an [[ion]] from one site to another through [[Crystallographic defect|defect]]s in the [[Crystal structure|crystal lattice]] of a solid. Ionic conduction is one aspect of [[current (electricity)|current]].<ref>Richard Turton. (2000).The Physics of Solids. New York:: Oxford University Press. ISBN 0198503520.</ref>
-{{cleanup-rewrite|date=October 2010}}
+In solids, ions typically occupy fixed positions in the crystal lattice and do not move. However, ionic conduction can occur, especially as the temperature increases.<ref>www.teknik.uu.se/ftf/education/Disordered_materials/Ion_conduction.pdf</ref>
-{{technical|date=October 2010}}
-{{Buzzword|date=July 2011}}
+Ionic conduction is one of the mechanisms by which [[microwave oven]]s are believed to work. Microwaves cause ions dissolved in the microwaved sample to [[oscillation|oscillate]], colliding with neighboring molecules or atoms. These collisions cause agitation or motion, or heat. This mechanism is "important when considering the heating behavior of  [[ionic liquid]]s" within a microwave.<ref>Kappe, C. O.; Stadler, A. Microwaves in Organic Synthesis and Medicinal Chemistry; Wiley-VCH: Weinheim, 2005. p. 12. ISBN 3527312102.</ref>
-'''Ionic conduction''' is the transit of [[ion]] (either cations or anions) from one site to another through defects in the [[Crystal structure|crystal lattice]] of a solid. Ionic conduction is one aspect of [[Current (electricity)|current]], which is the flow of charged particles through a material.<ref>Richard Turton. (2000).The Physics of Solids. New York:: Oxford University Press. ISBN 0198503520.</ref> In solids, ions typically occupy fixed positions in the crystal lattice, and therefore do not move. However, ionic conduction can occur, especially as the temperature of a solid increases.<ref>www.teknik.uu.se/ftf/education/Disordered_materials/Ion_conduction.pdf</ref>
+Ionic conduction in solids has been a subject of interest since the beginning of the 19th century. [[Michael Faraday]] established in 1839 that the laws of [[electrolysis]] are also obeyed in ionic solids like [[lead(II) fluoride]] ({{chemical formula|Pb||F|2}}) and [[silver sulfide]] ({{chemical formula|Ag|2|S}}).
-Ionic conduction is one of the mechanisms by which [[Microwave oven|microwave ovens]] are believed to work.<ref>Kappe, C. O.; Stadler, A. Microwaves in Organic Synthesis and Medicinal Chemistry; Wiley-VCH: Weinheim, 2005. ISBN 3527312102. </ref> During ionic conduction in the microwave, dissolved particles in the sample oscillate back and forth under the influence of the microwave, colliding with neighboring molecules or atoms. These collisions cause agitation or motion, creating heat. The ionic conductivity mechanism is very important when considering heating [[Ionic liquid|ionic liquids]] within a microwave.
+==Silver iodide==
-Ionic conduction in [[solids]] has been a subject of interest as early as the beginning of the 19th century. It was established by [[Michael Faraday]] (1839) that the laws of electrolysis are also obeyed in ionic solids like [[Lead (element)|Pb]][[Fluorine|F]]<sub>2</sub> and [[Silver (element)|Ag]]<sub>2</sub>[[Sulfur|S]]. There were, however, several important discoveries regarding ionic conduction phenomena in solids in the last century. For example, extraordinary high ionic conductivity in [[silver iodide]] was found by Tubandt et al. (1921) is of special importance. It was observed during the conductivity measurement of AgI that above 147 °C it transforms into a phase that exhibits an ionic conductivity of  <!--number and units needs fixing-->~ 1 –1&nbsp;cm<sup>−1</sup>, comparable to that of its [[liquid phase]]. Therefore, the high temperature phase of AgI is the first [[superionic]] conductor ever discovered. It was shown that a sub[[crystal structure|lattice]] [[cations|cationic]] disorder takes place in the highly conducting phase of AgI, which is now better known as <!--needs fixing-->-AgI. The liquid-like state of Ag<sup>+</sup> ions, as proposed by Strock (1934, 1936) and later reinforced by others (Geller, 1977; Funke, 1976), consists of a cubic unit cell of [[iodine]] ions, in which 6 [[octahedral]], 12 [[tetragonal]] and 24 [[trigonal bipyramid]]al, i.e., a total of 42 sites are available for 2 Ag<sup>+</sup> ions, as shown in the Figure 1. O' Keeffe and Hyde (1976) have argued that this [[phase transition]] in AgI is dramatic and powerful, nothing less than the melting and also shown that the [[entropy]] change at the superionic transition is comparable to its value at the melting. Thus, in the <!--needs fixing-->-phase I<sup>−</sup> ions form a bcc lattice and the Ag<sup>+</sup> ions are distributed in such a way that 42 [[crystallography|crystallographic]] equivalent interstices are available for the two Ag<sup>+</sup> ions.
+{{confusing|section|date=October 2007|reason=Some of the text makes no sense (e.g. "nothing less than the melting") and lacks sufficient explanation}}
+{{technical|section|date=October 2010}}
+In 1921, Tubandt et al. found that [[silver iodide]] ({{chemical formula|Ag||I}}) has extraordinary high ionic conductivity. While measuring conductivity, they found that above 147 &deg;C, AgI changes into a phase that has an ionic conductivity of <!--number and units needs fixing-->~ 1 –1&nbsp;cm<sup>−1</sup>, similar to that of its [[liquid phase]]. As a result, the high temperature phase of AgI was the first [[superionic conductor]] ever discovered. The highly conductive phase of AgI is now known as -AgI. It was shown that a sub[[crystal structure|lattice]] [[cations|cationic]] disorder takes place in -AgI. The liquid-like state of Ag<sup>+</sup> ions, as proposed by Strock (1934, 1936) and later reinforced by others (Geller, 1977; Funke, 1976), consists of a cubic [[crystal structure#Unit cell|unit cell]] of iodide ions (I<sup>-</sup>), in which a total of 42 sites (6 [[octahedral]], 12 [[tetragonal]] and 24 [[trigonal bipyramid]]al) are available for 2 Ag<sup>+</sup> ions, as shown in the Figure 1. O' Keeffe and Hyde (1976) have argued that this [[phase transition]] in AgI is dramatic and powerful, nothing less than the melting and have also shown that the [[entropy]] change at the superionic transition is comparable to its value at the melting. Thus, in the -phase, I<sup>−</sup> ions form a [[cubic crystal system|body-centered cubic]] lattice and the Ag<sup>+</sup> ions are distributed in such a way that 42 [[crystallography|crystallographic]] equivalent [[interstitial|interstices]] are available for the two Ag<sup>+</sup> ions.
-Soon alpha-phases of various materials like Ag<sub>2</sub>S, Ag<sub>2</sub>Se, Ag<sub>2</sub>Te, etc. were discovered (Tubandt, 1932). By the early 1930s, it was demonstrated that these fast ionically conducting solids could be treated entirely the same as [[aqueous]] [[electrolyte]]s from the viewpoint of chemical reactions and thermodynamics, hence these materials were also termed as solid electrolytes.
+[[Alpha phase]] crystals of various materials like {{chemical formula|Ag|2|s}}, {{chemical formula|Ag|2|se}}, {{chemical formula|Ag|2|Te}}, etc. were soon discovered (Tubandt, 1932). By the early 1930s, it was demonstrated that these [[fast ion conductor|fast ionically conducting]] solids could be treated entirely the same as [[aqueous]] [[electrolyte]]s from the viewpoint of [[chemical reaction]]s and [[thermodynamics]], hence these materials were labeled ''solid electrolytes''.
 ==References==
 <references/>
 {{DEFAULTSORT:Ionic Conductivity}}
 [[Category:Fundamental physics concepts]]
 [[ja:イオン移動度]]
+{{Physical-chemistry-stub}}
+{{Condensedmatter-stub}}