“…Throughout the past few decades, there has been extensive methodological developments to optimize its evaluation using a range of approaches varying in complexity, sophistication and accuracy. It is worthwhile mentioning some of the notable ones, such as pseudo-spectral scheme using Gaussian basis functions, multipole accelerated algorithm, LinK, truncated or short-range exchange kernels with/without the use of resolution-of-theidentity (RI) approximation, chain-of-sphere exchange based on quadrature, auxiliary density matrix, plane-wave basis functions, metropolis stochastic, pair-atomic RI, adaptively compressed exchange operator, density fitting with local domains, real-space with projection operators, rigorous integral screening, occupied-orbital fast multipole [24][25][26][27][28][29][30][31][32] , etc. The HF exchange energy density can be represented as,…”