Poly iodide

Self-assembly of poly iodide networks on templates with crown ethers, thia- and thiazacrown ethers as ligands 98CSR195. 

A soln. of twenty-two grains of iodine and thirty-three grains of iodide of potassium, in one ounce of distilled water forms the liquor iodi of the British Pharmacopoeia. The effects produced by the ammonium salts are attributed to their hydrolysis into ammonium hydroxide, and the consequent formation of ammonium iodide or polyiodide. The effects produced by soln. of the halide salts are doubtless due to the formation of poly iodides as in the analogous case with bromine and potassium bromide. A. A. Jakowkin allowed carbon disulphide to remain in contact with aq. soln. of iodine and potassium iodide until equilibrium was attained and... 

When iodine is dissolved in hydriodic acid or a soln. of a metallic iodide, there is much evidence of chemical combination, with the formation of a periodide. A. Baudrimont objected to the polyiodide hypothesis of the increased solubility of iodine in soln. of potassium iodide, because he found that an extraction with carbon disulphide removed the iodine from the soln. but S. M. Jorgensen showed that this solvent failed to remove the iodine from an alcoholic soln. of potassium iodide and iodine in the proportion KI I2, and an alcoholic soln. of potassium iodide decolorized a soln. of iodine in carbon disulphide. The hypothesis seemed more probable when, in 1877, G. S. Johnson isolated cubic crystals of a substance with the empirical formula KI3 by the slow evaporation of an aqueous-alcoholic soln. of iodine and potassium iodide over sulphuric acid. There is also evidence of the formation of analogous compounds with the other halides. The perhalides or poly halides—usually polyiodides—are products of the additive combination of the metal halides, or the halides of other radicles with the halogen, so. that the positive acidic radicle consists of several halogen atoms. The polyiodides have been investigated more than the other polyhalides. The additive products have often a definite physical form, and definite physical properties. J. J. Berzelius appears to have made the first polyiodide—which he called ammonium bin-iodide A. Geuther called these compounds poly-iodides and S. M. Jorgensen, super-iodides. They have been classified 1 as... 

A successful donor has been bis(ethylenedithio)tetrathiafulvalene (BEDT-TTF or ET). The structure of ET is depicted in Fig. 4-41. The infrared and Raman frequencies of BEDT-TTF and BEDF-TTF-t/g have been reported and assignments made (63). Figure 4-42 shows the Raman spectra of several salts in the region of 800-50 cm-1. Here, the research was done to determine the nature of the poly iodides in the molecule (64). 

Figure 51. The doping of poly-acethylene with iodine leads to the formation of a hole. Iodide (or poly-iodide) is the counterion.

The tri-iodides may be regarded as salts of the per halogen acids, but no hydrogen compound corresponding with the higher poly iodides have been obtained. 

Compounds of Tl have many similarities to those of the alkali metals TIOH is very soluble and is a strong base TI2CO3 is also soluble and resembles the corresponding Na and K compounds Tl forms colourless, well-crystallized salts of many oxoacids, and these tend to be anhydrous like those of the similarly sized Rb and Cs Tl salts of weak acids have a basic reaction in aqueous solution as a result of hydrolysis Tl forms polysulfides (e.g. TI2S5) and poly iodides, etc. In other respects Tl resembles the more highly polarizing ion Ag" ", e.g. in the colour and insolubility of its chromate, sulfide, arsenate and halides (except F), though it does not form ammine complexes in aqueous solution and its azide is not explosive. 

A great stmctural variety of solid and liquid polyiodides has been demonstrated in [1]. This review covers research activities related to the chemistry of poly iodide for the period from 1970 to 2002. The formation of anions containing more than one molecule of iodine is considered as resulting from the interaction between the components of basic building blocks (F, I2, Is ). 

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