Figure : Overlay of molecular geometries optimized with ωB97X-D4, 36,39,41 using the q-vSZP-v2 (blue) and def2-TZVPP 89 (light gray) basis set. The RMSE on the Cartesian q-vSZP-v2 coordinates with respect to the def2-TZVPP geometry is given in Ångström. For q-vSZP, numerical gradients generated by infinitesimal deflection of the Cartesian coordinates via a Python package written in-house were employed. Single-point energies were obtained via ORCA-6.0.0. The actual optimization was conducted with xtb 4 as a driver. The def2-TZVPP geometry optimization was conducted using analytical gradients in ORCA-6.0.0. reference structure, whereas the q-vSZP-v2 structure is kinked. A similar albeit less pronounced situation is the case for the cyanide group in complex b). Both observations can be attributed to the minimal basis set character of q-vSZP, potentially preventing some important hybridizations.