Low Temperature Physics: 38, 962 (2012); https://doi.org/10.1063/1.4758785 (4 pages)
Fizika Nizkikh Temperatur: Volume 38, Number 10 (October 2012), p. 1216-1220    ( to contents , go back )

Diffusion of H2 and Ne impurities in fullerite C60. Quantum effects

A.V. Dolbin, V.B. Esel'son, V.G. Gavrilko, V.G. Manzhelii, N.A.Vinnikov, and S.N. Popov

B. Verkin Institute for Low Temperature Physics and Engineering of the National Academy of Sciences of Ukraine, 47 Lenin Ave., Kharkov 61103, Ukraine
E-mail: dolbin@ilt.kharkov.ua
pos Анотація:

Received June 6, 2012

Abstract

The kinetics of sorption and subsequent desorption of normal H2 and Ne gases in a C60 powder has been investigated in the temperature interval 12–292 K by the method of direct pressure measurement. The measured characteristic times during which the octahedral interstitial sites of fullerite were occupied by the gas molecules were used to obtain the temperature dependences of the coefficients of H2 and Ne diffusion in fullerite. On going below room temperature the diffusion coefficients of the impurities first decreases in both the mixtures and then started to grow fast below 90 K (H2) and 100 K (Ne). The temperature dependence of the diffusion becomes weak at the lowest temperatures of the experiment. The features revealed are attributed to the competition between the thermally activated diffusion dominant at comparatively high temperatures and the quantum diffusion that prevails at low temperatures.

PACS: 68.43.Mn Adsorption kinetics.

Key words: quantum diffusion, sorption kinetics, fullerite C60, 4He.

Download 352861 byte View Contents