MCATDR    MCATDR    MCATDR    MCATDR    MCATDR    MCATDR    MCATDR    
          **********************************************
                    **************************
                              ******

SUBROUTINE MCATDR (T, X, IMCWRK, RMCWRK, TDR)
This subroutine computes the thermal diffusion ratios for the light
species into the mixture.

INPUT
T         - Real scalar, temperature.
               cgs units, K
X(*)      - Real array, mole fractions of the mixture;
            dimension at least KK, the total species count.
IMCWRK(*) - Integer workspace array; dimension at least LENIMC.
RMCWRK(*) - Real    workspace array; dimension at least LENRMC.

OUTPUT
TDR(*)    - Real array, thermal diffusion ratios for the species;
            dimension at least KK, the total species count.
            TDR(K) = 0 for any species with molecular weight less
            than 5.