MCMDIF    MCMDIF    MCMDIF    MCMDIF    MCMDIF    MCMDIF    MCMDIF    
          **********************************************
                    **************************
                              ******

SUBROUTINE MCMDIF (P, T, X, KDIM, IMCWRK, RMCWRK, D)
Returns the ordinary multicomponent diffusion coefficients,
given pressure, temperature, and mole fractions.

INPUT
P         - Real scalar, pressure.
               cgs units, dynes/cm**2
T         - Real scalar, temperature.
               cgs units, K
X(*)      - Real array, mole fractions of the mixture;
            dimension at least KK, the total species count.
KDIM      - Integer scalar, actual first dimension of D(KDIM,KK);
            KDIM must be at least KK, the total species count.
IMCWRK(*) - Integer workspace array; dimension at least LENIMC.
RMCWRK(*) - Real    workspace array; dimension at least LENRMC.

OUTPUT
D(*,*)    - Real matrix, ordinary multicomponent diffusion
            coefficients;
            dimension at least KK, the total species count, for
            both the first and second dimensions.
               cgs units, cm**2/s