Ab initio calculation of dc resistivity in liquid Al, Na and Pb

The dc conductivities of Al, Na and Pb in their liquid phase just above the melting point are calculated from first principles on the basis of density functional theory. We use the SIESTA code, molecular dynamics simulations with a Nose thermostat to generate representative structural snapshots in the liquid and Kubo–Greenwood formalism to calculate the optical conductivity. The dc conductivity comes from averaging the latter property over a number of structures and extrapolating to zero frequency. The calculated values fall within 1% of experimental data. A correction to the dipole matrix elements calculated via the momentum operator, due to non-locality of the pseudopotential, is very important for Na (where it increases the dc conductivity by about 75% to meet the experimental value), much smaller for Al and practically negligible for Pb.