Grafidino sob condições extremas de pressão: um estudo de dinâmica molecular

Abstract

In nanoscience, the study of materials under extreme conditions have become of great interest, to either understand the behavior of materials under such conditions and the develop new materials. The motivation for this work is to study the behavior of graphdiyne planes under high pressure conditions at different temperatures and the resulting structures' stability. This two-dimensional semiconductor nanostructure, designed in 1997 and synthesized for the first time in 2010, is formed by carbon atoms with sp and sp² hybridization. Because of the triple bonds present in its structure, graphdiyne exhibits a high reactivity under high pressure conditions, which can lead to the formation of covalent bonds between the sp-hybridized carbons in the different planes. In this work, the molecular dynamics method was applied to simulate and understand the process of formation of this new structure resulting from the interplanar bond formation of sp carbons. The simulations were performed using the ReaxFF (Reactive Force Field) reactive potential implemented in the LAMMPS (Large-scale Atomic/Molecular Massively Parallel Simulator) molecular dynamics package. For compression simulations, different temperatures have been employed, and it was observed that the temperature influenced the number of interplanar bonds, as well as its stability. Potential maps were also made for different distances from the planes, and it was possible to observe that the positions of minimum energy moved as the distance decreased, as it was also possible to observe in the simulations.