|dc.description.abstract||A new method for sampling the exact (within the nodal error) ground state distribution
and nondiflPerential properties of multielectron systems is developed and applied to firstrow
atoms. Calculated properties are the distribution moments and the electronic density
at the nucleus (the 6 operator). For this purpose, new simple trial functions are developed
First, using Hydrogen as a test case, we demonstrate the accuracy of our algorithm
and its sensitivity to error in the trial function. Applications to first row atoms are then
described. We obtain results which are more satisfactory than the ones obtained previously
using Monte Carlo methods, despite the relative crudeness of our trial functions.
Also, a comparison is made with results of highly accurate post-Hartree Fock calculations,
thereby illuminating the nodal error in our estimates.
Taking into account the CPU time spent, our results, particularly for the 8 operator,
have a relatively large variance. Several ways of improving the eflSciency together with
some extensions of the algorithm are suggested.||en_US