Comparative study of boson peak in normal and secondary alcohols with terahertz time-domain spectroscopy
Autor: | Tomobumi Mishina, Ryusuke Nozaki, Yoshiki Yomogida, Yuki Sato, Jun'ichiro Nakahara |
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Rok vydání: | 2010 |
Předmět: |
Permittivity
Materials science Condensed matter physics Terahertz radiation Relaxation (NMR) Dielectric Condensed Matter Physics Molecular physics Electronic Optical and Magnetic Materials Molecular vibration Dielectric loss Electrical and Electronic Engineering Terahertz time-domain spectroscopy Spectroscopy |
Zdroj: | Physica B: Condensed Matter. 405:2208-2212 |
ISSN: | 0921-4526 |
DOI: | 10.1016/j.physb.2010.02.010 |
Popis: | Using terahertz (THz) time-domain spectroscopy, we measured the complex permittivity of some normal (1-propanol, 1-butanol, and 1-pentanol) and secondary alcohols (2-propanol, 2-butanol, and 2-pentanol) in the frequency ranges from 0.2 to 2.5 THz at temperatures from 253 to 323 K. For all the samples, the complex permittivity in the THz region includes the following three components: (i) a high frequency side of dielectric relaxation processes, (ii) a broad mode around 1 THz, and (iii) a low frequency side of an intermolecular vibration mode located above 2.5 THz. The mode around 1 THz is recognized as a boson peak which is related to the local structure of disordered materials. The intensity of the boson peak in secondary alcohols is higher than that in normal alcohols. On the other hand, the number of carbon atoms slightly affects the appearance of the boson peak. These observations indicate that the position of an OH group in a molecule has a profound effect on the local structures in monohydric alcohols. |
Databáze: | OpenAIRE |
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