A program to generate a basis set adaptive radial quadrature grid for density functional theory

We present an automatic quadrature routine (AQR) which generates an atomic basis set adaptive radial quadrature grid for the numerical evaluation of molecular integrands in density functional theory. Unlike the popular radial grids that are tuned to a particular class of integrands and rely on a fixed selection of points, our grid adapts itself automatically to the atomic shell structure of any radial integrand and determines the best number of quadrature points that provides user specified accuracy. We evaluate the performance of our radial grid on various tight, diffuse, and noble gas atom radial integrands. We conclude that the radial quadrature grid generated by our AQR is generally comparable to and sometimes better than the best ranked popular radial grids in efficiency and reliability.