#Authors: Piyush Sharda (Leiden) 2024
burn_cell_metal_chem integrates a primordial+metal ISM chemistry network
for a single set of initial conditions. The density, temperature, and composition
are set in the inputs file, as well as the maximum time to integrate.
This test does not include cosmic rays and photochemistry.
Upon completion, the new state is printed to the screen.
For metal chemistry, state.xn is always assumed to contain number densities. We work with number densities and not mass fractions because our equations are very stiff (stiffness ratios are as high as 1e31) because y/ydot (natural timescale for a species abundance to vary) can be very different (by factors ~ 1e30) for different species. However, state.rho still contains the density in g/cm^3, and state.e still contains the specific internal energy in erg/g/K.
The code is built with the metal_chem network and run with inputs_metal_chem.