Robert Kurucz’s website[^1]. ATLAS9 [@kurucz01] handles the line opacity with the opacity distribution functions (ODF), which greatly simplifies and reduces the computation time [@strom01; @kurucz04; @castelli02]. ATLAS uses the mixing-length scheme for convective energy transport. It consists in pretabulating the line opacity as function of temperature and gas pressure in a given number of wavelength intervals which cover the whole wavelength range from far ultraviolet to far infrared. For computational reasons, in each interval the line opacities are rearranged according to strength rather than wavelength. For each selected metallicity and microturbulent velocity, an opacity distribution function table has to be computed. While the computation of the ODFs is very time consuming, extensive grids of model atmospheres and spectrophotometric energy distributions can be computed in a short time once the required ODF tables are available.

ATLAS12 [@kurucz04; @castelli03] uses the opacity sampling method (OS) to calculate the opacity at 30,000 points. The high resolution synthetic spectrum at a selected resolution can then be obtained by running SYNTHE [@kurucz03]. More recently, @lester01 have developed SATLAS\_\_ODF and SATLAS\_\_OS, the spherical version of both ATLAS9 and ATLAS12, respectively. No extensive grids of models have been published up to now, neither with ATLAS12, nor with 