Dynamic of transformation under the heat treatment of a new carbon phase carbolite studied by calorimetry and X-ray powder diffraction

Abstract We report on the specific heat, C(T) , measurements of a new carbon phase carbolite in the temperature ranges 4.5K T T C(T) dependence does not follow the Debye law. For the adequate description of the measured low temperature C(T) dependence, the chain-like crystal structure of the carbolite crystals has been considered, and the model of specific heat for quasi-one-dimensional crystals has been used. By means of X-ray and high temperature specific heat measurements it has been found that carbolite is a metastable phase under the normal conditions, undergoing the irreversible complicated transformations to the amorphous state upon heating above T ≈350K.