  We have calculated a grid of photospheric phase atmospheres of Type Ia
supernovae (SNe Ia) with metallicities from ten times to one thirtieth the
solar metallicity in the C+O layer of the deflagration model, W7. We have
modeled the spectra using the multi-purpose NLTE model-atmosphere and
spectrum-synthesis code, PHOENIX. We show models for the epochs 7, 10, 15, 20,
and 35 days after explosion. When compared to observed spectra obtained at the
approximately corresponding epochs these synthetic spectra fit reasonably well.
The spectra show variation in the overall level of the UV continuum with lower
fluxes for models with higher metallicity in the unburned C+O layer. This is
consistent with the classical surface cooling and line blocking effect due to
metals in the outer layers of C+O. The UV features also move consistently to
the blue with higher metallicity, demonstrating that they are forming at
shallower and faster layers in the atmosphere. The potentially most useful
effect is the blueward movement of the Si II feature at 6150 Angstrom with
increasing C+O layer metallicity. We also demonstrate the more complex effects
of metallicity variations by modifying the 54Fe content of the incomplete
burning zone in W7 at maximum light. We briefly address some shortcomings of
the W7 Finally, we identify that the split in the Ca H+K feature produced in W7
and observed in some SNe Ia is due to a blending effect of Ca II and Si II and
does not necessarily represent a complex abundance or ionization effect in Ca
II. amodel when compared to observations.
