Turbospectrum is a 1D LTE spectrum synthesis code which covers 600 molecules, is fast with many lines, and uses the treatment of line broadening described by Barklem & O’Mara (1998).
http://adsabs.harvard.edu/abs/1998A%26A...330.1109A and http://adsabs.harvard.edu/abs/2012ascl.soft05004P