Samir F Matar*

Lebanese German University (LGU), Sahel-Alma, Jounieh, Lebanon

*Corresponding Author: Samir F Matar, Lebanese German University (LGU), Sahel-Alma, Jounieh, Lebanon.

Received: November 28, 2022; Published: December 06, 2022

Abstract

From crystal chemistry rationale and first principles investigations, novel tetragonal carbon allotrope C5 with mixed sp²/sp²–like carbon sites hybridizations is identified as cohesive and stable both dynamically and mechanically with metallic behavior. Charge density distribution is localized at tetrahedral C-sp³ and delocalized with π-like electrons between trigonal C-sp² leading to metallic like electronic behavior The anisotropic structure resulting from vertically aligned C=C (ethylene –like) along the tetragonal c-axis provide large C33 elastic constant and high Vickers hardness with a magnitude slightly below diamond. The properties of novel simple allotrope should help assessing nanodiamonds with mixed sp²/sp³ C investigated in different fields of materials as electrochemical ones.

Keywords: Diamond; Hardness; Phonons; DFT; Crystal Chemistry

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Citation

Citation: Samir F Matar. “Novel Ultrahard Carbon Allotrope C5 with Mixed sp2/sp3 Carbon Hybridizations. Crystal chemistry and First Principles Investigations". Acta Scientific Applied Physics 3.1 (2022): 02-09.

Copyright

Copyright: © 2022 Samir F Matar. This is an open-access article distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited.