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The structures considered in the present work were armchair and zigzag α-GNT and γ-GNT , with tube lengths varying from 55 up to 193 Å, and with diameter values from 9 up to 69 Å. These structures are representative of the diverse structural and electronic GNT behaviors. For comparison purposes, similar CNT structures (in terms of length, diameter, and chirality values) were also considered. The torsional tube properties were obtained from the analysis of molecular dynamics simulations carried out using the LAMMPS code, and with the atomistic interactions described by the reactive force field ReaxFF. Charge distributions were calculated based on geometry and connectivity using the electronegativity equalization method. The behavior of the GNT under mechanical twisting and the torsional stiffness values were obtained from the analysis of the second derivative of the torsional strain energy as a function of the torsion angle θ, calculated around the equilibrium angles. The energy variation was calculated subtracting the current total energy of the twisted tube from the total energy of the original non-twisted tube.