Structural stability and electron‐phonon coupling in two‐dimensional carbon allotropes at high electronic and atomic temperatures

Several two-dimensional carbon allotropes have been recently fabricated experimentally, triggering various innovative research and technological applications. The properties of such 2d materials under extreme conditions are to a large extent unknown. In this work, we study theoretically the effects of high electronic and atomic temperatures on free-standing graphene, pentaheptite, and biphenylene network. We analyse the limits of their structural stability with respect to thermal and nonthermal damage. With a state-of-the-art approach, we calculate the electronic heat capacity and the electron-phonon coupling parameter dependent on both electronic and atomic temperatures. The knowledge of these parameters may facilitate modelling of various two-dimensional carbon allotropes under laser pulse irradiation, improving understanding of their behaviour in experimental applications.