Construction of the Fock Matrix on a Grid-Based Molecular Orbital Basis Using GPGPUs

We present a GPGPU implementation of the construction of the Fock matrix in the molecular orbital basis using the fully numerical, grid-based bubbles representation. For a test set of molecules containing up to 90 electrons, the total HartreeFock energies obtained from reference GTO-based calculations are reproduced within 10(-4) E-h to 10(-8) E-h for most of the molecules studied. Despite the very large number of arithmetic operations involved, the high performance obtained made the calculations possible on a single Nvidia Tesla K40 GPGPU card.