High-Pressure Structural Transformations of Carbyne

Abstract

The structure of cumulenic carbyne samples is studied by x-ray diffraction after exposure to high temperatures and pressures (200-900 ° C, 7.7 GPa). The results indicate that, with increasing temperature, carbyne transforms from a highly disordered to x-ray amorphous state, with narrower diffuse bands. At high temperatures, a disordered graphite-like structure is formed, with a density substantially lower than that of graphite. The behavior of impurities during the structural transformation of carbyne is discussed.