Year: 2011
Type: article
Abstract: Atomic motion of guest atoms inside semiconducting clathrate cages is considered an important source for glasslike thermal behavior. ${}^{69}$Ga and ${}^{71}$Ga nuclear magnetic resonance studies on type I Ba${}_{8}$Ga${}_{16}$Sn${}_{30}$ show a clear low-temperature relaxation peak attributed to the influence of Ba rattling dynamics on the framework-atom resonance, with a quadrupolar relaxation mechanism as the leading contribution. Data are analyzed using a two-phonon Raman process, according to a recent theory involving localized anharmonic oscillators. Excellent agreement is obtained using this model, with the parameters corresponding to a uniform array of localized oscillators with very large anharmonicity.
Source: Physical Review B
Institution: Texas A&M University
Language: English
Subfield: Materials Chemistry
Field: Materials Science
Domain: Physical Sciences
Open Access status: bronze
OpenAlex ID: W2174598511