Novel hyperdense orthorhombic C10 with ultrahigh hardness, and physical properties close to Diamond: Crystal chemistry and DFT investigations.
Discuss this preprint
Start a discussion What are Sciety discussions?Listed in
This article is not in any list yet, why not save it to one of your lists.Abstract
Based on crystal chemistry search and density functional theory (DFT), an original orthorhombic C 10 allotrope is proposed with ultra-high density of 3.75 g/cm 3 (versus 3.54 g/cm 3 for diamond) and ultra-high Vickers hardness (H V = 100 GPa versus 95 GPa for Diamond). Such properties pertain to the exceptional arrangement of distorted C4 tetrahedra connected by short d(C-C) = 1.51 Å, opposite to diamond characterized by corner sharing tetrahedra. The resulting structure has unknown topology. Phonon band structures show highest optic modes of 40 THz close to experimental diamond Raman line. The calculated specific heat C V curve shows shape agreement with experimental diamond values. The electronic band structure exhibits indirect band gap of 3 eV confirming semi-conducting C 10 versus insulating diamond.
