LTBOUNDLIBXC

TBOUNDLIBXC = .TRUE. | .FALSE.
Default: TBOUNDLIBXC = .FALSE.

Description: TBOUNDLIBXC specifies whether or not the lower bound for the Kohn-Sham kinetic-energy density $\tau _{\sigma }$ ( $\tau _{\sigma }^{\textrm {W}}<\tau _{\sigma }$ ) is enforced before $\tau _{\sigma }$ is used in a meta-GGA functional from Libxc.

The Kohn-Sham kinetic-energy density $\tau _{\sigma }$ should in principle be larger than the von Weizsäcker kinetic-energy density $\tau _{\sigma }^{\textrm {W}}$ . However, for numerical reasons this may not always be the case and can potentially lead to problems depending on the meta-GGA. When TBOUNDLIBXC=.TRUE., $\tau _{\sigma }=\max(\tau _{\sigma },\tau _{\sigma }^{\mathrm {W} })$ is applied before $\tau _{\sigma }$ is used in a meta-GGA functional from Libxc.