Infrared study on the metal – insulator transition in filled skutterudites RRu 4 P 12 ð R 1⁄4 Pr ; Sm Þ
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چکیده
Infrared study has been made on the filled skutterudites PrRu4P12 and SmRu4P12; which undergo a metal–insulator (M–I) transition at TMI 1⁄4 60 and 16 K; respectively. The opening of a charge gap for the two compounds are clearly observed below TMI: For PrRu4P12; new phonon peaks are also observed below TMI; which suggests that the crystal symmetry is lowered. On the other hand, no additional peaks appear in the insulating phase for SmRu4P12: These results indicate that the mechanism of M–I transition of SmRu4P12 is different from that of PrRu4P12: r 2003 Elsevier B.V. All rights reserved. PACS: 71.30.+h; 75.30.Mb; 78.20.Ci
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تاریخ انتشار 2004