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Progress was made on two fronts. First, on the “resonance” front, my student Daniel Whitenack and I showed how the exact lifetime of the lowest-energy resonance of unbound electronic systems is encoded into a complex “density” that can be obtained via complex-coordinate scaling. We illustrated  this with one-electron examples (see our recent paper in JPCL) and showed how the lifetime can be extracted from the complex density in much the same way as the ground-state energy of bound systems is extracted from its ground-state density.  We have also established the self-consistent set of complex Kohn-Sham equations designed to yield the correct complex density of the interacting system. We have solved these equations for a couple of different cases of interacting electrons, and are making progress toward a more general implementation. Daniel received a best P-Chem student poster award at the past ACS meeting for the presentation of his work. He also tutored Michael Mack, an undergraduate student who worked with us during the summer, and will continue now as a 1st-year graduate student.

Second, on the “partition” front, with my postdoc Yu Zhang, we used the recently developed Partition Density Functional Theory (PDFT) to examine how the shape and dipole of the PDFT fragment densities are preserved as the environment changes, and compared with other partitioning schemes. Our results show that (1) the transferability of PDFT densities is about an order of magnitude higher than that of real-space partitioning schemes, and (2) the PDFT dipoles are about an order of magnitude more transferable than Hirshfeld dipoles in regions of chemical relevance.  A paper about this was accepted for publication in JCTC.  We are now working on the extension of the Perdew-Parr-Levy-Balduz ensemble to the cases studied by Daniel, so that our PDFT algorithm can be applied to metastable anions as well.