X, Y, Z Calculator
[Fe/H]
X:
(Hydrogen mass fraction)
Y:
(Helium mass fraction)
Y; helium mass fraction (if you need it to be different)
Z:
(Heavy mass fraction)
[Li/Fe]
Source for Standard Abundances
[Be/Fe]
Anders & Grevesse 1989
[B/Fe]
Sauval et al. 1996
[C/Fe]
Asplund 2004
[N/Fe]