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Understanding of the phase transformation from fullerite to amorphous carbon at the microscopic level

M. Moseler·H. Riedel·P. Gumbsch·J. Staring·B. Mehlig
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Abstract

We have studied the shock-induced phase transition from fullerite to a dense amorphous carbon phase by tight-binding molecular dynamics. For increasing hydrostatic pressures P, the C60-cages are found to polymerise at P<10 GPa, to break at P~40 GPa and to slowly collapse further at P>60 GPa. By contrast, in the presence of additional shear stresses, the cages are destroyed at much lower pressures (P<30 GPa). We explain this fact in terms of a continuum model, the snap-through instability of a spherical shell. Surprisingly, the relaxed high-density structures display no intermediate-range order.

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M. Moseler, H. Riedel, P. Gumbsch, J. Staring, B. Mehlig. 2004-09-24. Understanding of the phase transformation from fullerite to amorphous carbon at the microscopic level. https://doi.org/10.1103/physrevlett.94.165503

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