Phonon spectrum and vibrational characteristics of linear nanostructures in solid matrices
| Autor: | E. V. Manzhelii, Kseniia Minakova, Igor Gospodarev, S. B. Feodosyev, E. S. Syrkin |
|---|---|
| Jazyk: | angličtina |
| Rok vydání: | 2015 |
| Předmět: |
Materials science
Physics and Astronomy (miscellaneous) Condensed matter physics Condensed Matter - Mesoscale and Nanoscale Physics Phonon Van Hove singularity General Physics and Astronomy FOS: Physical sciences Carbon nanotube Heat capacity law.invention Crystal Matrix (mathematics) 10th International Conference on Cryocrystals and Quantum Crystals (Final part) law Mesoscale and Nanoscale Physics (cond-mat.mes-hall) Physics::Atomic and Molecular Clusters Molecule Surface layer |
| Zdroj: | Scopus-Elsevier |
| Popis: | The atomic dynamics of linear chains embedded in a crystalline matrix or adsorbed on its surface is studied. A linear chain formed by substitutional impurities in a surface layer and at the same time offsetting from this layer was analyzed particularly. This system models the actively studied experimentally structures in which gas molecules are adsorbed on the walls of the bundles of carbon nanotubes located in certain medium. It is shown that the quasi-1D features are typical for the chains in which the interatomic interaction is higher than the interaction between the atoms of the chain and the atoms of the crystal matrix. On the local phonon density of atoms of the chain, the transition to quasi-one-dimensional behavior has the form of the kink. In other words, it is the first (lowest-frequency) van Hove singularity, which in 3D structures (the system under consideration is generally three-dimensional) corresponds to the transition from closed to open constant-frequency (quasi-plane) surfaces. The local phonon densities of atoms in the chain have one-dimensional character at frequencies higher than the frequency of the van Hove singularity. The rms-amplitude of embedded chains atoms vibrations is calculated and the behavior of the atomic vibrations contribution in the low-temperature heat capacity of the system is analyzed. 14 pages, 7 figures |
| Databáze: | OpenAIRE |
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