However, as explained below, we found practical issues in implementing the SGT algorithm. First, conversion of the integral representation of the long-range term into a finite sum using the Gauss-Hermite quadrature becomes challenging for higher target accuracy, since many quadrature nodes are required to cover the integral range where the integrand approaches zero via the Gaussian weight factor. This leads to impractically large number of cubature nodes, and due to the finite precision of variable, it becomes difficult to achieve the target accuracy. Another issue is with the treecode approach.