Finding Partition Potentials

Partition Density Functional Theory is a formally exact approach to partitioning molecules into fragments via functional minimization and constraints on fragment densities. Cohen and Car proposed a Dynamical Optimization Algorithm for Partition Theory inspired by the Car-Parrinello Method of electronic structure [1]. We modify this algorithm to incorporate a reference HOMO wave-function calculation as a guide to obtain the partition potential, a global quantity arising as the Lagrange multiplier that guarantees satisfaction of the density constraint. We report on the implementation of this procedure for one-dimensional systems, and possible implications for linear-scaling electronic-structure calculations.\\[4pt] [1] M. H. Cohen, and R. Car, J. Phys. Chem. A 2008, 112, 571-575