We analyze breaking of symmetries that belong to the double point
group D
![$_{\mbox{\rm\scriptsize {2h}}}^{\mbox{\rm\scriptsize {TD}}}$](img3.gif)
(three mutually perpendicular symmetry axes of the
second order, inversion, and time reversal). Subgroup structure of
the D
![$_{\mbox{\rm\scriptsize {2h}}}^{\mbox{\rm\scriptsize {TD}}}$](img3.gif)
group indicates that there can be as much as 28 physically
different, broken-symmetry mean-field schemes -- starting with
solutions obeying all the symmetries of the D
![$_{\mbox{\rm\scriptsize {2h}}}^{\mbox{\rm\scriptsize {TD}}}$](img3.gif)
group, through 26
generic schemes in which only a non-trivial subgroup of D
![$_{\mbox{\rm\scriptsize {2h}}}^{\mbox{\rm\scriptsize {TD}}}$](img3.gif)
is
conserved, down to solutions that break all of the D
![$_{\mbox{\rm\scriptsize {2h}}}^{\mbox{\rm\scriptsize {TD}}}$](img3.gif)
symmetries. Choices of single-particle bases and the corresponding
structures of single-particle hermitian operators are discussed for
several subgroups of D
![$_{\mbox{\rm\scriptsize {2h}}}^{\mbox{\rm\scriptsize {TD}}}$](img3.gif)
.