  We examine the global performance of an extended self-consistent mean field
theory of 2+ excitations in even-even nuclei. 518 nuclei are included in our
survey, comprising all but 39 of the known nuclei tabulated by Raman et al. The
theory is based on a quantal collective Hamiltonian in five dimensions in which
the potential energy and the tensor of inertia are obtained from constrained
triaxial Hartree-Fock-Bogoliubov calculations. The only parameters in theory
are those of the finite-range, density-dependent Gogny D1S interaction. The
following properties of the lowest 2+ excitations are calculated: excitation
energy, reduced transition probability, and spectroscopic quadrupole moment. We
find that the theory is very reliable to classify the nuclei by shape.
Quantitatively the performance of the theory in deformed nuclei is excellent:
average excitation energies and transition quadrupole moments are within 5% of
the experimental values, and the dispersion about the averages are 20% and 10%,
respectively. The performance is not as good on spherical and soft nuclei.
Including all nuclei in the performance evaluation, the average transition
quadrupole moment is 10% too high and the dispersion about the mean is 20%. For
the energies, the average is 13% too high and the dispersion is 40%.
