On nonadiabatic SCF calculations of molecular properties

TL;DR

This paper critiques the DEMO method for nonadiabatic SCF calculations, highlighting that improper removal of center of mass motion can lead to inaccuracies and misleading virial theorem indications.

Contribution

It identifies a key flaw in the DEMO method related to center of mass removal, impacting the accuracy of molecular property calculations.

Findings

Improper center of mass removal affects DEMO accuracy

Virial theorem may be misleading in this context

Highlights need for proper center of mass treatment

Abstract

We argue that the dynamic extended molecular orbital (DEMO) method may be less accurate than expected because the motion of the center of mass was not properly removed prior to the SCF calculation. Under such conditions the virial theorem is a misleading indication of the accuracy of the wavefunction.