It is well known that the chemisorption of various chlorosilane materials on glass atomic storage vessel walls results in surface coatings which inhibit electronichyphen; and nuclearhyphen;spin relaxation. In the present study the chemical reaction of rubidium, and by analogy other alkali metals, with dichlorodimethylsilanehyphen;treated glass surfaces has been studied. We find evidence that rubidium reacts with a freshly prepared coating to produce H2and a volatile siliconhyphen;containing species. The most reasonable reaction process is postulated to be rubidium reacting with residual silanol groups (Sihyphen;OH) found on the surface. As the reaction proceeds these groups would disappear, thus reducing the spinhyphen;relaxation rate associated with the surface. We believe that this reaction results in the lsquo;lsquo;curingrsquo;rsquo; of wall coatings reported by other investigators. Concurrently, the gaseous reaction products become impurities within the system. The spinhyphen;relaxation cross section of the siliconhyphen;containing species is expected to be less than 1times;10minus;17cm2.
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