Depressurization amorphization of single-crystal boron carbide.
نویسندگان
چکیده
We report depressurization amorphization of single-crystal boron carbide (B4C) investigated by in situ high-pressure Raman spectroscopy. It was found that localized amorphization of B4C takes place during unloading from high pressures, and nonhydrostatic stresses play a critical role in the high-pressure phase transition. First-principles molecular dynamics simulations reveal that the depressurization amorphization results from pressure-induced irreversible bending of C-B-C atomic chains cross-linking 12 atom icosahedra at the rhombohedral vertices.
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ورودعنوان ژورنال:
- Physical review letters
دوره 102 7 شماره
صفحات -
تاریخ انتشار 2009