The strongly constrained and appropriately normed (SCAN) meta-generalized gradient approximation (meta-GGA) functional is a milestone achievement of electronic structure theory. Recently, a revised and restored form $\left({\mathrm{r}}^2\mathrm{SCAN}\right)$ has been suggested as a replacement for SCAN in high-throughput applications. Here, we assess the accuracy and reliability of the ${\mathrm{r}}^2\mathrm{SCAN}$ meta-GGA functional for the group-IV elemental solids carbon (C), silicon (Si), germanium (Ge), and tin (Sn). We show that the ${\mathrm{r}}^2\mathrm{SCAN}$ functional agrees closely with its parent functional SCAN for elastic constants, bulk moduli, and phonon dispersions, but the numerical stability of ${\mathrm{r}}^2\mathrm{SCAN}$ is superior. Both meta-GGA functionals outperform standard GGA (Perdew-Burke-Ernzerhof) in terms of accuracy and approach the level of common hybrid functionals (Heyd-Scuseria-Ernzerhof). However, we find that ${\mathrm{r}}^2\mathrm{SCAN}$ performs much worse than SCAN for the $\alpha \leftrightarrow \beta$ phase transition of both Ge and Sn, yielding larger phase energy differences and transition pressures.

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• Pressure effects
• Structural phase transition
• Elemental semiconductors
• Density functional calculations
• Meta-GGA