Fig. 10: The zero temperature equations of state of two solid phases of niobium.

Black curve: VASP results on body-centered cubic bcc-Nb vs the experimental results from ref. 45 (experiment 1, empty squares) and ref. 47 (experiment 2, bullets). The error bars of experiment 1 are smaller than the size of the symbol. Magenta curve: VASP results on orthorhombic Pnma-Nb. The Pnma-Nb curve is shifted up by 100 GPa for clarity.