  Theoretical stellar libraries have been increasingly used to overcome
limitations of empirical libraries, e.g. by exploring atmospheric parameter
spaces not well represented in the latter. This work presents a new theoretical
library which covers 3000 $\leq$ Teff $\leq$ 25000\,K, -0.5 $\leq$ log g $\leq$
5.5, and 12 chemical mixtures covering 0.0017 $\leq$ Z $\leq$ 0.049 at both
scaled-solar and $\alpha$-enhanced compositions. This library complements
previous ones by providing: (i) homogeneous computations of opacity
distribution functions, models atmospheres, statistical surface fluxes and high
resolution spectra; (ii) high resolution spectra with continua slopes corrected
by the effect of predicted lines, and; (iii) two families of $\alpha$-enhanced
mixtures for each scaled-solar iron abundance, to allow studies of the
$\alpha$-enhancement both at `fixed iron' and `fixed Z' cases. Comparisons to
observed spectra were performed and confirm that the synthetic spectra
reproduce well the observations, although there are wavelength regions which
should be still improved. The atmospheric parameter scale of the model library
was compared to one derived from a widely used empirical library, and no
systematic difference between the scales was found. This is particularly
reassuring for methods which use synthetic spectra for deriving atmospheric
parameters of stars in spectroscopic surveys.
