Hartree-Fock-Bogolyubov solutions corresponding to the tetrahedral
deformation were found in six tetrahedrally doubly-magic nuclei:
Zr,
Zr,
Zr,
Ba,
Yb, and
Th. Results with four Skyrme forces, SLy4, SkM*, SIII, and
SkP, sometimes significantly differ in the values of
,
depths of the tetrahedral minima, and their energies with respect to
the co-existing quadrupole solutions. The inclusion of pairing
reduces the depths, or even suppresses the existence of the
tetrahedral minima. In Zr isotopes, the tetrahedral minima are rather shallow,
but some forces predict them as the lowest in energy. In
Ba,
they are not lower than 7MeV above the quadrupole solutions, but in
Yb and
Th that minimum distance is reduced to 3MeV.
Tetrahedral minima in
Ba,
Yb, and
Th are
estimated to be deeper than in the Zr isotopes.