The molecular electric dipole, quadrupole and octupole moments of a selected
set of 21 spin-compensated molecules are determined employing the extended
version of the Piris natural orbital functional 6 (PNOF6), using the
triple-ζ Gaussian basis set with polarization functions developed by
Sadlej, at the experimental geometries. The performance of the PNOF6 is
established by carrying out a statistical analysis of the mean absolute errors
with respect to the experiment. The calculated PNOF6 electric moments agree
satisfactorily with the corresponding experimental data, and are in good
agreement with the values obtained by accurate ab initio methods, namely, the
coupled-cluster single and doubles (CCSD) and multi-reference single and double
excitation configuration interaction (MRSD-CI) methods.Comment: 3 figure