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Updated: Aug 23, 2026

Fabrication and Optimization of Type II Silicon Clathrate Films
Published on: October 14, 2025
Exceptional ideal strength of carbon clathrates
X Blase1, Philippe Gillet, A San Miguel
1Laboratoire de Physique de la Matière Condensée et des Nanostructures, Université Claude Bernard Lyon I and CNRS, 43 Bd du 11 Novembre 1918, 69622 Villeurbanne Cedex, France. xblase@lpmcm.univ-lyon1.fr
Abstract:
We study by means of ab initio calculations the ideal tensile and shear strengths of the C-46 clathrate phase. While its bulk modulus and elastic constants are smaller than in diamond, its strength is found to be in all directions larger than the critical stresses associated with the diamond [111] planes of easy slip. This can be related to the frustration by the clathrate cage structure of the diamond to graphite instability under nonhydrostatic stress conditions [corrected] The criteria for designing strong materials are discussed.
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