Meta-GGA that describes weak interactions in addition to bond energies and band gaps
Timo Lebeda, Stephan Kümmel
Abstract
We show that the recently proposed Lebeda-Aschebrock-Kümmel (LAK) meta-generalized gradient approximation, the accuracy of which was previously established for atomization energies, bond lengths, and band gaps, also captures weak interactions near equilibrium without a dispersion correction. We discuss how this is achieved. Furthermore, we show that among the semilocal cost pure functionals, LAK is the one that reaches the highest accuracy for the large GMTKN55 database for general thermochemistry and kinetics. Next, we explain the design strategy of enhancement factor engineering. Its key idea is to complement exact constraints with construction principles. Finally, we discuss areas of research in which the use of LAK may offer advantages over existing functionals.