We present model atmospheres and theoretical spectra for X-ray bursters .
Our models include the effects of Compton scattering on free electrons .
The atmospheres have compositions that are mixtures of hydrogen , helium , and iron .
For our models the ratio of color temperature , T _ { c } , to effective temperature , T _ { eff } , is in the range 1.2 - 1.8 .
This ratio depends on T _ { eff } , surface gravity , and iron abundance .
For fixed T _ { eff } and surface gravity , models with non-zero iron abundance exhibit values of T _ { c } / T _ { eff } that are slightly lower than pure hydrogen-helium models .