Halogenoargentate ions

Halogenoargentate(I) ions, 37 1-2 connectivity relationships, 37 4-5 dinculear anions... 

Mononuclear anions, halogenocuprate 1) and halogenoargentate(I) ions four-coordinated metal centers, 37 19 three-coordinated metal centers, 37 7-11 Mononuclear iron-sulfur clusters, 47 219 EPR spectra, 47 423-425 EPR spectra, 47 448... 

In the following presentation, solid-state structures documented hitherto for halogenocuprate(I) and halogenoargentate(I) ions are described in order of increasing coordination number of the metal, Possible correlations between the coordination number of copper(I) or silver(I) in the anion and properties of the cation with which it is coprecipitated, such as size, shape, and exposure of the positive charge, are then discussed. 

Bonding in linear dihalogenocuprate(I) (1, 2, 47-49) and di-halogenoargentate(I) (47-49) ions has been discussed in terms of ds hybridization of the metal atom. A theoretical study of the bonding and nuclear quadrupole coupling in [CuCl2] and [CuBr2]" has demon-... 

Discrete trinuclear halogenocuprate(I) or halogenoargentate(I) species containing solely three-coordinated metal centers have not been reported hitherto. An [Ag3I6]3 ion in which one of the silver(I) atoms is three coordinated, whereas the remaining two exhibit tetrahedral coordination geometry has, however, recently been isolated (81) (cf Section II,C,3). 

Extreme diversity is exhibited in the coupling of metal halide tetra-hedra to form polymeric halogenocuprate(I) and halogenoargentate(I) ions, there being an abundance of different types of infinite chains, layers, and three-dimensional arrays. Because the object of this article is to focus on variations in metal coordination number, and, in particular, on trends associated with the nature of the cation, structural description will be limited to those types of polymeric anion most frequently encountered hitherto in crystalline halogenocuprates(I) and halogenoargentates(I). 

Analogous halogenoargentate(I) [M2X3] ions have been determined in [N(C2H5)4][Ag2Cl3] (137), [N(CH3)4][Ag2Br3] (138),... 

Rationalization of the detailed geometry of the particular halogeno-cuprate(I) or halogenoargentate(I) ion in terms of the influence of cation shape or positive charge distribution is, however, much more complex. Whereas it has proved possible to employ cations predictively for anion design in series of compounds containing comparable cations, e.g., symmetrically substituted tetraalkylammonium and phosphonium analogs (cf. 60, 71, 72), it seems doubtful that cations of disparate shape can be used as other than predictors of metal(I) coordination number. 

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