How Ambiguous Is the Local Kinetic Energy?

The local kinetic energy and the closely related local electronic stress tensor are commonly used to elucidate chemical bonding patterns, especially for covalent bonds. We use three different approaches-transformation properties of the stress tensor, quasiprobability distributions, and the virial theorem from density-functional theory-to clarify the inherent ambiguity in these quantities, discussing the implications for analyses based on the …