AI Article Synopsis
- A pentagonal covalent network made of sp² and sp³ carbon atoms was studied using density functional theory and found to be a metastable 3D carbon structure.
- This network has impressive mechanical properties, including a high bulk modulus of 381 GPa and negative Poisson's ratio of -0.241, with Young's and shear moduli of 1691 and 1113 GPa, surpassing diamond's.
- The network acts as a semiconductor with an indirect band gap of 2.52 eV and relatively low carrier masses, occurring between the L and X points in its electronic structure.
Article Abstract
A pentagonal covalent network consisting of sp^{2} and sp^{3} C atoms has been investigated based on the density functional theory. Our theoretical investigations clarified that the pentagonal covalent network is a metastable three-dimensional carbon allotrope with the Fm3[over ¯]m space group possessing remarkable mechanical properties: relatively high bulk modulus of 381 GPa together with a negative Poisson's ratio of -0.241. Accordingly, the pentagonal covalent network possesses extremely high Young's and shear moduli of 1691 and 1113 GPa, respectively, surpassing those of the diamond. The electronic structure of the pentagonal network is a semiconductor with an indirect band gap of 2.52 eV between L and X points for valence and conduction band edges, respectively, with the relatively small carrier masses.
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| http://dx.doi.org/10.1103/PhysRevLett.125.016001 | DOI Listing |
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