  The recently developed iterated stockholder atoms (ISA) approach of
Lillestolen and Wheatley (Chem. Commun. {\bf 2008}, 5909 (2008)) offers a
powerful method for defining atoms in a molecule. However, the real-space
algorithm is known to converge very slowly, if at all. Here we present a
robust, basis-space algorithm of the ISA method and demonstrate its
applicability on a variety of systems. We show that this algorithm exhibits
rapid convergence (taking around 10--80 iterations) with the number of
iterations needed being unrelated to the system size or basis set used.
Further, we show that the multipole moments calculated using this basis-space
ISA method are as good as, or better than those obtained from Stone's
distributed multipole analysis (J. Chem. Theory Comput. {\bf 1}, 1128 (2005) ),
exhibiting better convergence properties and resulting in better behaved
penetration energies. This can have significant consequences in the development
of intermolecular interaction models.
