  The expensive cost of computing exact exchange in periodic systems limits the
application range of density functional theory with hybrid functionals. To
reduce the computational cost of exact change, we present a range-separated
algorithm to compute electron repulsion integrals for Gaussian-type crystal
basis. The algorithm splits the full-range Coulomb interactions into
short-range and long-range parts, which are respectively computed in real and
reciprocal space. This approach significantly reduces the overall computational
cost as integrals can be efficiently computed in both regions. The algorithm
can efficiently handle large numbers of k points with limited CPU and memory
resources. As a demonstration, we performed an all-electron k-point
Hartree-Fock calculation for LiH crystal with 1 million Gaussian basis
functions, which was completed on a desktop computer in 1400 CPU hours.
