TY - JOUR
T1 - Guest ion motion in cage structure crystals investigated by Raman scattering
AU - Udagawa, Masayuki
AU - Hasegawa, Takumi
AU - Takasu, Yuichi
AU - Ogita, Norio
AU - Suekuni, Koichiro
AU - Avila, Marcos A.
AU - Takabatake, Toshiro
AU - Ishikawa, Yoshikazu
AU - Takeda, Naoya
AU - Nemoto, Yuichi
AU - Goto, Terutaka
AU - Sugawara, Hitoshi
AU - Kikuchi, Daisuke
AU - Sato, Hideyuki
AU - Sekine, Chihiro
AU - Shirotani, Ichimin
AU - Yamaura, Jun Ichi
AU - Nagao, Yohei
AU - Hiroi, Zenji
PY - 2008/1/1
Y1 - 2008/1/1
N2 - Last five years we have mainly investigated phonons in the following cage compounds by Raman scattering: RT4X12, A 8Ga16Ge30, La3Pd20Ge 6, RB6, KOs2O6. From this systematic investigation we have clarified the following dynamical properties of the guest ion trapped in the large cages. The vibration of the guest ion is highly anharmonic due to weak atomic interaction between the guest ion and cage atom. This anharmonicity universally decreases the vibration energy of the guest ion with decreasing temperature. The existence of carriers decreases the interaction between the guest atoms and changes the dispersion curve of the guest ion mode to flat, which is the experimental evidence of the weak interaction between the guest atoms. For thermoelectricity, it is found in A8Ga 16Ge30 that the off-center rattling decreases lattice thermal conductivity.
AB - Last five years we have mainly investigated phonons in the following cage compounds by Raman scattering: RT4X12, A 8Ga16Ge30, La3Pd20Ge 6, RB6, KOs2O6. From this systematic investigation we have clarified the following dynamical properties of the guest ion trapped in the large cages. The vibration of the guest ion is highly anharmonic due to weak atomic interaction between the guest ion and cage atom. This anharmonicity universally decreases the vibration energy of the guest ion with decreasing temperature. The existence of carriers decreases the interaction between the guest atoms and changes the dispersion curve of the guest ion mode to flat, which is the experimental evidence of the weak interaction between the guest atoms. For thermoelectricity, it is found in A8Ga 16Ge30 that the off-center rattling decreases lattice thermal conductivity.
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U2 - 10.1143/JPSJS.77SA.142
DO - 10.1143/JPSJS.77SA.142
M3 - Article
AN - SCOPUS:46949097418
SN - 0031-9015
VL - 77
SP - 142
EP - 147
JO - journal of the physical society of japan
JF - journal of the physical society of japan
IS - SUPPL.A
ER -