Low Temperature Physics: 36, 370 (2010); https://doi.org/10.1063/1.3432243 (3 pages)
Физика Низких Температур: Том 36, Выпуск 5 (Май 2010), c. 470-473    ( к оглавлению , назад )

Novel mechanism of the negative thermal expansion of doped fullerite C60

M.A. Strzhemechny and I.V. Legchenkova

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: strzhemechny@ilt.kharkov.ua

Received February 9, 2010


A model for an atomic impurity in an octahedral void of fullerite C60 is suggested. The problem is solved in the spherical oscillator approximation, which is appropriate for the larger rare gas atoms. It is shown that such impurities can contribute to the negative thermal expansions at low temperatures and produce a Schottky-like maximum at higher temperatures.

PACS: 81.05.ub Fullerenes and related materials;
PACS: 61.72.jj Interstitials;
PACS: 65.40.–b Thermal properties of crystalline solids.

Key words: fullerite, rare gas atoms, negative thermal expansion.