| Autor: |
Pugachev, A. T., Churakova, N. P., Gorbenko, N. I., Saadli, Kh., Syrkin, E. S. |
| Předmět: |
|
| Zdroj: |
Journal of Experimental & Theoretical Physics; Nov98, Vol. 87 Issue 5, p1014, 5p |
| Abstrakt: |
The thermal expansion coefficient α and structure of C[sub 60] films with thickness t∼3-10 nm were investigated in the temperature interval from room to liquid-nitrogen temperature by electron-optical methods. The thermal expansion coefficient was determined from the temperature shift of the diffraction maxima in the electron diffraction patterns. The objects of investigation were epitaxial C[sub 60] films condensed in vacuum on a (100) NaC1 cleavage surface and oriented in the (111) plane. A surface-induced size effect in the thermal expansion coefficient was observed. It was established that as t decreases α[sub f] increases and is described well by the relation α[sub f]=17·10[sup -6] K[sup -1] + 8.3·10[sup -5] nm K[sup -1] t[sup -1]. This relation was used to estimate the linear expansion coefficient α[sub s] of the C[sub 60] surface in the (111) plane as α[sub s] = 60·10[sup -6] K[sup -1], which is several times larger than the bulk value. The experimental results agree satisfactorily with the theoretical calculations of the mean-square displacements of molecules located in a region near the surface. [ABSTRACT FROM AUTHOR] |
| Databáze: |
Complementary Index |
| Externí odkaz: |
|
