Arsonium ions structure

The approximately tetrahedral arrangement of the bonds around the As( V) in the disulfide structure becomes the exactly tetrahedral arrangement in (C6H5)4AsI (407). The structure of this arsonium iodide consists of two interpenetrating body-centered lattices, one of (C6Hs)4As+ and the other of I. Each tetrahedral arsonium ion is surrounded by eight iodide ions at a... 

Recently, the preparation of salts of the bis(tetrathiotungsto)nickelate (II) ion, Ni(WS4)J2, has been reported and the tetraphenylphosphonium and -arsonium salts isolated. The structure shown in Fig. 17 has been proposed for this anion196. ... 

X-ray and spectroscopic studies indicate that the arsonium halides are ionic. Mc4AsBr consists of tetrahedral Mc4As+ units and separate bromide ions. X-ray structures have also been obtained on a series of tetraphenylarsonium salts. " A regular tetrahedral stmcture is found about the arsenic atom when the counterion is a halide or ion of similar size. However, as the size of the counterion increases, the crystals become more disordered. In solution, tetraphenylarsonium salts are almost completely dissociated, but ion pairing can be significant and is dependent primarily on the dielectric constant of the solution. 

The reactions of the chalcogen(IV) halides are quite variable due to their high general reactivity, their remarkable structural and bonding properties, and the specific influence of the inert pair as an electronic chamaeleon on the reaction paths and products. As examples, important reaction types that will be addressed besides the ones mentioned above are (X = chalcogen, Y = halogen, = metal ions or large cations such as tetraphenylphosphonium(arsonium), triphenylmethyl, tetrabutylammonium, etc.)... 

---