Finite temperature electronic properties of diamond-like carbon materials*

Accurate calculations of electron-phonon coupling are essential to predict the finite temperature (T) properties of materials and molecules with light atoms. We present an approach to compute electron-phonon coupling where the electronic structure is treated from first principles, e.g. at the DFT level of theory, and nuclear quantum effects are incorporated using either path-integral molecular dynamics or molecular dynamics with a quantum thermostat [1]. In particular, we carried out simulations for diamond, diamondoids, and amorphous carbon by coupling the first-principle molecular dynamics code Qbox (http://qboxcode.org) with i-PI (http://ipi-code.org), a path integral simulation package. We illustrate the role of anharmonicity and disorder in determining electron-phonon coupling, and we compare the zero-temperature limit of our simulations with the results recently reported at T=0 [2].
[1] M. Ceriotti, G. Bussi, and M. Parrinello, Phys. Rev. Lett., 103, 030603 (2009).
[2] R.McAvoy, M. Govoni, and G. Galli, J. Chem. Theory Comput, 14, 6269 (2018).