Hartree potential Journal Article 2 Research Support, Non-U.S. Gov't 2 Poisson solver 1 charge density 1 conjugate gradients 1 density functional theory 1 mehr ... fast multipole method 1 graphics processing unit 1 heterogeneous computing 1 interpolating scaling functions 1 linear scaling 1 many integrated core 1 multigrid 1 parallel fast Fourier transform 1 parallelization 1 weniger ...