Some aspects of the solid state physics of yellow arsenic

ChemInform Abstract: Some Aspects of the Solid State Physics of Yellow Arsenic

<title>Influence of treatment on stability of electrochromic WO<formula><inf><roman>3</roman></inf></formula> film in acidic electrolyte</title>

The influence of exposure in vacuum of 10-2 - 10-3 Pa and temperature treatment at 720 - 730 K in water vapor atmosphere on stability of tungsten oxide films in 0.1 N H2SO4 electrolyte were studied. The processes that take place during the film exposure in vacuum, determine the reduction of charge injection at the constant voltage change condition. In the case of temperature treatment the opposite changes of charge injection were observed. This indicates to opposite processes in films during both expositions. According to exposures characters, they could be a reduction of tungsten oxide initiated by oxygen evacuation from film in vacuum and film oxidation in water vapor media at high temper…

Spectroscopic studies of molecular arsenic

Formation of As8 dimers in molecular solid-state arsenic

Abstract Molecular yellow arsenic (y-As) consists of tetrahedral As 4 molecules that may be packed in various ways. All y-As modifications, both disordered and crystalline, are metastable and undergo irreversible transitions (polymerization) under action of heat and light, which cause a change in the nature of bonding in the molecules. Polymerization of y-As leads to the formation of amorphous arsenic (a-As) possessing a continuous random network structure. DTA studies show that polymerization is an activated exothermic process. The value of its enthalpy agrees satisfactorily with an estimate of the excess energy of strained ‘banana-shaped’ bonds in an As 4 molecule. Quantum chemical calcul…