In this contribution, we present the calculation of the superconducting transition temperature, T_c, by means of the Roeser-Huber formula [1,2] solely using availabe crystallographic data and details of the electronic configuration. Here, we focus on the specific case of lanthanum (La) which superconducts at T_c = 4.8 K when it is double hexagonal closed packed (dhcp-structure) as compared to T_c = 6 K when being face-centered cubic (fcc-structure). Using the Roeser-Huber approach, these two different T_c’s can nicely be reproduced which demonstrates the usefulness of this approach offering an easy and relatively simple calculation procedure. This further enables to check the crystal structures best suited for superconductivity with the highest T_c. The Roeser-Huber equation can thus straightforwardly be integrated on machine-learning-based searches for new superconductors, or, to validate existing predictions.

[1] H. P. Roeser et al., Acta Astron. 67, 1333-1336 (2010).
[2] M. R. Koblischka et al., Metals 10, 158 (2020).

Keywords: Superconductors, Transition temperature, Lanthanum, Roeser-Huber equation