2023/11/12 by Samir F. Matar, Matar, Samir F.
Earth and Planetary Sciences · Materials Science · #Boron and Carbon Nanomaterials Research #Diamond and Carbon-based Materials Research #FOS: Physical sciences #High-pressure geophysics and materials #Materials Science (cond-mat.mtrl-sci)
paper · pdf · doi:10.48550/arxiv.2311.06924
openalex publication_date 2023/11/12 · openalex created_date 2023/11/15 · openalex updated_date 2026/07/28
Based on crystal engineering and density functional theory DFT calculations a transformational pathway is proposed from qtz (quartz-based) topology characterized by distorted tetrahedra to dia (diamond-like) regular tetrahedra topology. The protocol consists of carbon insertions into orthorhombic (space group P222, No. 16) within C5, C6, and C7, leading to ultimate C8 identified as diamond-like. The induced structural and physical changes are assessed with elastic properties pointing to ultra hardness, larger for qtz-C6 than dia-C8, whilst intermediate C7 is compressible due to its diamond-defective structure. The dynamic stability was shown from the phonons, and thermodynamic quantities as the specific heat CV was addressed in comparison with diamond experimental data. The electronic band structures reveal semi-conducting C6, metallic C7 characterized by diamond-defect structure, and insulating C8.