Q-Chem Webinar 33

New Effective Core Potential Capabilities in Q-Chem 5

Simon McKenzie
Presented by Simon McKenzie on

Simon McKenzie did a joint-degree undergraduate between the Australian National University and the National University of Singapore. He completed his honours year under the supervision of Prof. Peter Gill working on the efficient computation of ECP integrals. He underwent an internship at Q-Chem in Pleasanton, California where he worked closely with Dr. Evgeny Epifanovsky to implement his honours research into the new Q-Chem integral library libqints. Simon is now in the second year of his PhD under Prof. Peter Gill, for which he has been awarded a Westpac Future Leaders Scholarship.


Effective core potentials (ECPs) are crucial in applying quantum chemical methods to heavier elements. The associated ECP integrals are among the most difficult one-electron integrals to calculate. In Q-Chem 5.0, a new state-of-the-art ECP integral engine was introduced, exploiting efficient screening and recurrence relations. In this webinar, I will briefly discuss the theory behind this new ECP integral engine, demonstrate the additional ECP capabilities and give some practical tips for the use of ECPs in your research.