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The effect of the shock wave loading on films of amorphous carbyne was investigated. Chemically synthesized films were deposited on 1 mm thick copper disks. X-ray and transmission electron microscopy studies of 10 and 150 micron carbyne films recovered after shock loading at pressures of 18, 26 and 36 GPa. Ten micron films partially transformed to carbyne crystals with a size of 1 micron. Thick films of carbyne transformed to a mixture of amorphous carbon phase and nanocrystalline cubic diamond.

Abstract: Shock compressibility of C60 fullerite and sound velocities in shock-compressed fullerite were experimentally studied at the pressures range up to ∼50 GPa. In our experiments, we used polycrystalline C60 specimens with a density of 1.64 g/cc. The Hugoniot of C60 fullerite had a set of peculiarities, which may be attributed to a series of polymorphic phase transitions. The jump of sound velocity in shocked C60 at pressure ∼9 GPa indicates the formation of a rather hard carbon phase. It is possible to assume that it is a polymerized C60 phase. In the region of pressures 9–25 GPa, destruction of this phase and formation of a graphite-like carbon occurs. With further growth of shock pressure, phase transition of the graphite-like carbon to a diamond-like phase is observed with a transition onset pressure ∼25 GPa. If shock pressures are higher than ∼33 GPa, Hugoniot of C60 fullerite is determined by the thermodynamic properties of the diamond-like phase. [Copyright &y& Elsevier]

Abstract: A new semiempirical equation of state for the simple cubic phase of C60 fullerite is proposed. A critical analysis of calculated results in comparison with available high-temperature, high-pressure experimental data is made. Physical–chemical transformations observed in recent experiments on shock compression of C60 fullerite are discussed in view of equation-of-state calculations for the simple cubic phase of C60 fullerite as well as for the graphite and diamond phases of carbon. [Copyright &y& Elsevier]