Sparse approximate matrix-matrix multiplication for density matrix purification with error control
Anton G. Artemov, Emanuel H. Rubensson · Journal of Computational Physics · 2021
We propose an accelerated density matrix purification scheme with error control. The method makes use of the scale-and-fold acceleration technique and screening of submatrix products in the block-sparse matrix-matrix multiplies to reduce the computational cost. An error bound and a parameter sweep are combined to select a threshold value for the screening, such that the error can be controlled. We evaluate the performance of the method in comparison to purification without acceleration and without submatrix product screening.