Atomic and molecular calculations using quasirandom numbers

We have calculated the total ground-state energy, kinetic energy, and poten tial energy of He. H-2, Li, and Be using explicitly correlated wavefunction s and two numerical integration procedures. The first integration procedure uses pseudorandom numbers and converges as N-0.5. The second uses a set of quasirandom. numbers generated by Halton's algorithm. Under some circumsta nces the convergence of this integration procedure can be as fast as N-1. W hen a small to intermediate number of quasirandom. numbers are used, most o f our expectation values converge faster than those computed using pseudora ndom numbers. When a large number of quasirandom numbers are used. however, we find that most of the expectation values converge at roughly the same r ate as those computed using pseudorandom numbers. (C) 2001 Academic Press.