Silver perchlorate 412 Subject

Tetracarbonyl cations [Cr(CO)4(L2)]+, where L2 represents arylphosphines, alkyl, or aryl phosphites, or a bidentate ligand with phosphorus or arsenic donor atoms, have been produced by both chemical and electrochemical means. However, oifly one of these complexes, namely, tra i -[Cr(CO)4(PPh3)2]+, is stable enough to be isolated as the perchlorate salt. Exposure to light and moisture produces tra i -Cr(CO)4(PPh3)2 via disproportionation. Just as easily isolated, but somewhat less sensitive, are the [Cr(CO)3(PR3)3]+ cations. " Oxidation with a silver ion or NO+ converts the /uc-(R3 = Me2Ph, (OMe)3) and mer-(R3 = (OMe)3, (OMe)2Ph, (OPh)3) complexes into Cr products with mer structures. Light and heat promote the formation of reduced wer-Cr(CO)3 (PR3)3. These tetra(carbonyl) and tri(carbonyl) cations have been the subject of ESR spectroscopy and theoretical study. 

Haissinsky and Walen [35] subjected nitrogen iodide to 5-MeV a-particles from a polonium source. The dryness of the sample and the intensity of the source decreased the time to explosion. The investigators stated that "the detonation of nitrogen iodide could be explained by a local heating of a grain of the powder." However, they thought this was an exceptional result because lead azide, silver azide, and diazo-zw-nitroaniline perchlorate did not detonate from 1 mCi of Po within 20 min. In lead azide a yellowing of the material occurred. 

Finally, it should be said that the above-discussed osmotic pressure-forced retention of one of the components of a mixture subjected to separation according to size exclusion mechanism does not exclude the possibility of true retention-type solute/sorbent interactions. Hypercrosslinked polystyrene may well enter attractive interactions with soft and lipophilic (chaotropic [163]) anions, such as sulfide, thiosulfate, rhodanide, perchlorate, tetrafluoroborate, and hexafluorophosphate. Also, some cations such as silver, copper, and mercury may interact with the aromatic 71-systems of the polystyrene matrix, which will retard the movement of the ions. These interactions may contribute to the separation of the ions from their stiU larger competing ions, but they may also be counterproductive to the size exclusion effect and deteriorate the separation of the retarded ions from smaller species. 

---