We analyze breaking of symmetries that belong to the double point
group D
(three mutually perpendicular symmetry axes of the
second order, inversion, and time reversal). Subgroup structure of
the D
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
group, through 26
generic schemes in which only a non-trivial subgroup of D
is
conserved, down to solutions that break all of the D
symmetries. Choices of single-particle bases and the corresponding
structures of single-particle hermitian operators are discussed for
several subgroups of D
.