Example: Athermal, gas phase, reversible reaction
~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~

.. math::

  \text{A}(g) ↔ \text{R}(g)

Notes:

 * Species database names and aliases are defined on single lines.
 * The forward and backward reactions are defined separately.
 * The heats of reaction are defined as zero (athermal) and explicitly assigned to
   the gas phase.

.. code-block:: none

    NMAX_g = 2
    Species_g(1) = "A" "R"
    Species_Alias_g(1) = "A" "R"

    ! No. of gas phase species
    ! Database names
    ! Species aliases

    @(RXNS)             !  Begin reaction block
    fwd_AtoR {          !  Reaction 1 construct
    chem_eq = "A --> R" !  Chemical Reaction Eq
    DH = 0.0            !  (cal/moles-reacted)
    fracDH(0) = 1.0     !  Gas phase HoR
    }                   !  End reaction 1 construct
    rvs_AtoR {          !  Reaction 2 construct
    chem_eq = "R --> A" !  Chemical Reaction Eq
    DH = 0.0            !  (cal/moles-reacted)
    fracDH(0) = 1.0     !  Gas phase HoR
    }                   !  End reaction 2 construct
    @(END)              !  End reaction block