Communication: Calibration of a strong-correlation density functional on transition-metal atoms

In recent work [A. D. Becke, J. Chem. Phys. 138, 074109 (2013)], a suite of density functionals for static, dynamical, and strong correlation was introduced. The strong-correlation part is intended to describe dissociating chemical systems using symmetry-restricted orbitals, and was calibrated on spin- and spatially-symmetrized open-shell atoms of the first and second rows. This Communication extends the calibration of our functionals to transition-metal atoms by including all open-shell atoms through the third row. We find that the theory works well for transition-metal atoms also. The new concomitant parametrization will be applied to problems of chemical interest in upcoming work.