The Beryllium spectral region of the Sun , Procyon and 4 stars in the open cluster NGC6633 up to T { } _ { eff } = 7500K have been synthesised using atlas 9 model atmospheres and the moog spectral synthesis program .

The line list used for these syntheses has been modified from the atlas 9 line list to improve the quality of the fits in light of the improved opacities in the new version of the moog code .

Significant changes have been made to the Mn i line at atlas 9 wavelength 3131.037 \AA and an OH line has been added at 3131.358 \AA .
In addition there are a number of minor changes to gf -values throughout the synthesised region thus improving the fit for the spectra across the temperature range considered .