Accuracy of electronic density calculated using an optimally tuned range-separated hybrid functional

We provide a quantitative study of the accuracy of the electronic density calculated using density functional theory. Specifically, we consider the recently developed optimally tuned range-separated hybrid (OT-RSH) functional approach. We calculate dipole moments using OT-RSH functional across a database of 152 polar molecules and compare them to literature coupled-cluster calculations with single and double excitations and perturbative triples (CCSD(T)) data. We also consider another test set of 14 closed-shell diatomic molecules to quantify the performance of OT-RSH functional in predicting the electronic densities using CCSD densities as a reference. We find that OT-RSH functional-derived electronic densities and dipole moments are as accurate as some better performing global hybrid functionals. Also, OT-RSH overcomes the empiricism and limited predictive power associated with the arbitrary choice of the amount of Fock exchange in the traditional global hybrid functional.

Automated summary

We quantitatively studied the accuracy of electronic density calculated using the optimally tuned range-separated hybrid (OT-RSH) functional method in this research. The dipole moments of 152 polar molecules were calculated using the OT-RSH functional and compared with literature coupled-cluster calculations. Another test set consisting of 14 closed-shell diatomic molecules was used to evaluate the performance of OT-RSH in predicting electronic densities. The results showed that OT-RSH-derived electronic densities and dipole moments were as accurate as some better performing global hybrid functionals, overcoming the limitations of empirical choices in traditional global hybrid functionals.