Accession Number : ADA191945

Title :   Alkali Reactions with Wall Coating Materials Used in Atomic Resonance Cells.

Descriptive Note : Technical rept.,

Corporate Author : AEROSPACE CORP EL SEGUNDO CA CHEMISTRY AND PHYSICS LAB

Personal Author(s) : Camparo, J C ; Frueholz, R P ; Jaduszliwer, B

PDF Url : ADA191945

Report Date : 30 Dec 1987

Pagination or Media Count : 22

Abstract : It is well known that the chemisorption of various chlorosilane materials on glass atomic storage vessel walls results in surface coatings that inhibit electronic and nuclear spin relaxation. In the present study the chemical reaction of rubidium, and by analogy other alkali metals, with dichloro-dimethylsilane-treated glass surfaces has been studied. We find evidence that rubidium reacts with a freshly prepared coating to produce H2 and a volatile silicon-containing species. The most reasonable reaction process is postulated to be rubidium reacting with residual silanol groups (Si-OH) found on the surface. As the reaction proceeds these groups would disappear, thus reducing the spin relaxation rate associated with the surface. We believe that this reaction results in the curing of wall coatings reported by other investigators. Concurrently, the gaseous reaction products become impurities within the system.

Descriptors :   *ALKALI METAL COMPOUNDS, *CHEMICAL REACTIONS, *COATINGS, *RUBIDIUM, *WALLS, ALKALI METALS, CELLS, CHEMISORPTION, CURING, ELECTRONS, GASES, IMPURITIES, NUCLEAR RESONANCE, RATES, REACTANTS(CHEMISTRY), RELAXATION, RESPONSE, SILICON COMPOUNDS, SPIN STATES, SURFACE FINISHING, VOLATILITY

Subject Categories : Organic Chemistry
      Physical Chemistry

Distribution Statement : APPROVED FOR PUBLIC RELEASE