  A calculus for the derivatives of the eigen values of the neutralino mass
matrix with respect to the CP violating background fields is developed and used
to compute the mixings among the CP even and the CP odd Higgs sectors arising
from the inclusion of the neutralino sector consisting of the neutralino, the Z
boson, and the neutral Higgs bosons ($\chi^0_i-Z-h^0-H^0$) exchange in the loop
contribution to the effective potential including the effects of large CP
violating phases. Along with the stop, sbottom, stau and chargino-W-charged
Higgs ($\chi^+-W-H^+$) contributions computed previously the present analysis
completes the one loop corrections to the Higgs boson mass matrix in the
presence of large phases. CP violation in the neutral Higgs sector is discussed
in the above framework with specific focus on the mixings of the CP even and
the CP odd sectors arising from the neutralino sector. It is shown that
numerically the effects of the neutralino exchange contribution on the mixings
of the CP even and the CP odd sectors are comparable to the effects of the stop
and of the chargino exchange contributions and thus the neutralino exchange
contribution must be included for a realistic analysis of mixings in the CP
even and the CP odd sectors. Phenomenological implications of these results are
discussed.
