The diffusion of OH in silica glass tubes was studied at temperatures of between 1500 and 2300C via high spatial resolution laser beam measurements of the 0.00273mm optical absorption of the glass. By fitting the measured radial OH profiles to calculated diffusion distributions, it was found that the results could be described by the expression:

D (cm2/s) = 2.51 x 10-5 exp[-15100K/T]

J.Kirchhof, P.Kleinert, W.Radloff, E.Below: Physica Status Solidi A, 1987, 101[2], 391-401