The migration of D and H was measured by using a steady-state method. It was found that both isotopes moved towards the cooler end. The heat of transport of H was equal to 43.3kJ/mol for temperatures of between 370 and 430C, while the heat of transport of D was equal to 53.0kJ/mol for temperatures of between 360 and 420C.
Thermomigration of Hydrogen and Deuterium in Vanadium, its Alloys, Niobium and Tantalum. H.Nakajima, M.Yoshioka, M.Koiwa: Transactions of the Japan Institute of Metals, 1987, 28[12], 949-56
Table 166
Diffusivity, Mobility and Effective Charge of H in Ta
Temperature (C) | m (cm2/Vs) | D (cm2/s) | Z*(e) |
26 | 2.0 x 10-5 | 1.73 x 10-6 | 0.3 |
50 | 4.6 x 10-5 | 2.5 x 10-6 | 0.5 |
100 | 7.9 x 10-5 | 4.2 x 10-6 | 0.6 |
150 | 1.09 x 10-4 | 6.8 x 10-6 | 0.6 |
250 | 2.6 x 10-4 | 1.5 x 10-5 | 0.8 |
600 | 1.25 x 10-3 | 6.1 x 10-5 | 1.5 |