Mechanical properties, strength physics and plasticity

Features of dependence of Raman spectra of cluster structures of three-dimensionally polymerized fullerite on pressure

F. S. Khorobrykh^ab, V. D. Churkin^ab, M. Yu. Popov<sup>ab

a</sup> Moscow Institute of Physics and Technology (National Research University), Dolgoprudny, Moscow Region
^b Technological Institute for Superhard and Novel Carbon Materials, Troitsk, Moscow

Abstract: We study the effect of high hydrostatic pressure on 3D polymerized fullerite C$_{60}$. We do not observe further structural changes until 150 GPa after a formation of 3D C$_{60}$ under hydrostatic pressure 28 GPa. It is experimentally shown that the obtained samples consist of different clusters formed by $sp^3$ bonds with a different set of force constants, the values of which vary within 20% and exceed the diamond force constants by the factor of 1.3–1.5. The influence of the exposure of laser radiation on the process of 3D polymerization of C$_{60}$ under pressure was found. Increasing of the exposure by the factor of 15 leads to a decrease in the bulk modulus of 3D C$_{60}$ from 610 GPa to 504 GPa.

Keywords: bulk modulus, ultrahard fullerite, high pressures, Raman spectroscopy.

Received: 20.09.2021
Revised: 29.10.2021
Accepted: 29.10.2021

DOI: 10.21883/FTT.2022.02.51933.207

Bibliographic databases:

•