Low Temperature Physics: 42, 401 (2016); https://doi.org/10.1063/1.4951701
The part of acoustic phonons in the negative thermal expansion of the layered structures and nanotubes based on them
V.V. Eremenko1, A.F. Sirenko2, V.A. Sirenko1, A.V. Dolbin1, I.A. Gospodarev1, E.S. Syrkin1, S.B. Feodosyev1, I.S. Bondar1, and K.A. Minakova3
1B. Verkin Institute for Low Temperature Physics and Engineering of NAS Ukraine 47 Prospekt Nauky, Kharkiv 61103, Ukraine
2V. N. Karazin National University, Kharkiv 61077, Ukraine
3National Technical University “Kharkiv Polytechnic Institute”, 21 Bahaliy Str., Kharkov 61002, Ukraine
Received February 8, 2016
A negative linear thermal expansion observed experimentally in a number of crystalline compounds with a complicated lattice and anisotropic interaction between atoms. The nature of negative linear thermal expansion along a number of directions is explained on the basis of calculations which were carried out at a microscopic level. We analyze anomalies in the temperature dependence of the coefficients of linear thermal expansion (the LTEC) along different directions: in layered crystals, formed as a monoatomic layers (graphite and carbon nanofilms) and multilayer “sand-wiches” (dichalcogenides of transition metals); in multilayer crystal structures such as high-temperature super-conductors in which the anisotropy of the interatomic interaction is not saved in the long-range order; in carbon nanotubes. The results of theoretical calculations are compared with the data of x-ray, neutron diffraction and dilatometric measurements.
PACS: 63.20.–e Phonons in crystal lattices.
Key words: interatomic interaction in crystals, phonon spectrum, quasiharmonic dynamics of the crystal lattice, thermal expansion.
Published online: March 23, 2016
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ISSN: 0132-6414 (Print) | ISSN: 1816-0328 (Online)