LuRh 2 Si 2 : Sensitivity of the Fermi surface to the Si z ‐position

We present band structure calculations of the non‐magnetic compound LuRh 2 Si 2 which serves as a reference for YbRh 2 Si 2 , a prototypical material for the investigation of quantum critical points. The relative z position of the Si atoms is found to have a strong impact on the band structure and the Fermi surface topology. We find the total energy to be minimized for z  = 0.381 c whereas a comparison of predicted extremal orbits with Shubnikov–de Haas frequencies shows best agreement at the experimental value z  = 0.379 c . We therefore recommend usage of z  = 0.379 c for future electronic structure calculations of LuRh 2 Si 2 and YbRh 2 Si 2 .