Structural model of the boron carbide solid solution

Abstract

Recent experiments support a previously proposed model of the location of carbon within the boron carbide structure as a function of carbon concentration. The main features of the model are the presence of carbon within icosahedral units over the entire single phase region, and the progressive replacement of CBC chains with CBB chains as the concentration is reduced from B4C to B13C2. This model provides a unified understanding of the results of a diverse set of experiments. In particular, electrical and thermal transport measurements, acoustic velocity measurements, powder and single crystal x‐ray diffraction, and Raman, infrared, and 13C NMR spectroscopy, are discussed in terms of their relation to the model.