TY - JOUR
T1 - Preparation and electronic states of Na16Ba8Si 136 clathrate
AU - Rachi, Takeshi
AU - Tanigaki, Katsumi
AU - Kumashiro, Ryotaro
AU - Winter, Johannes
AU - Kuzmany, Hans
N1 - Funding Information:
The synchrotron radiation experiments were performed by the approval of the Japan Synchrotron Radiation Research Institute (JASRI) as Nanotechnology Support Project. This work was supported by Creation of Nano Devices and Systems Based on New Physical Phenomena and Functional Principles of CREST of JST. The present work is also partially supported by the Tohoku University 21 century COE program ‘Particle-Matter Hierarchy’ of MEXT, Japan. This work was performed by a Grant-in-Aid from the Ministry of Education, Science, and Culture of Japan, no. 13304031.
PY - 2005/6/20
Y1 - 2005/6/20
N2 - A Si136 compound with an endohedral accommodation of Ba is newly made and its electronic states are compared to those of pure silicon-network superconducting Ba8Si46. The resulting Na 16Ba8Si136 has indeed a small density of states at the Fermi level and does not superconduct down to 2 K. Rietveld analyses show that Ba is accommodated in a Si28 cage with 0.98 occupancy and Na in Si20 with 0.61. The disappearance of superconductivity could be explained in terms of the little hybridization of Ba 5d/6s with Si28 polyhedral cluster orbitals, leading to a very low density of states at the Fermi level.
AB - A Si136 compound with an endohedral accommodation of Ba is newly made and its electronic states are compared to those of pure silicon-network superconducting Ba8Si46. The resulting Na 16Ba8Si136 has indeed a small density of states at the Fermi level and does not superconduct down to 2 K. Rietveld analyses show that Ba is accommodated in a Si28 cage with 0.98 occupancy and Na in Si20 with 0.61. The disappearance of superconductivity could be explained in terms of the little hybridization of Ba 5d/6s with Si28 polyhedral cluster orbitals, leading to a very low density of states at the Fermi level.
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U2 - 10.1016/j.cplett.2005.04.076
DO - 10.1016/j.cplett.2005.04.076
M3 - Article
AN - SCOPUS:19844371973
VL - 409
SP - 48
EP - 51
JO - Chemical Physics Letters
JF - Chemical Physics Letters
SN - 0009-2614
IS - 1-3
ER -