SUBROUTINE DWNFR0(ID)
C     =====================
C
C     Auxiliary quantities for dissolved fractions
C
      INCLUDE 'PARAMS.FOR'
      INCLUDE 'MODELP.FOR'
      PARAMETER (UN=1.,SIXTH=UN/6.,CCOR=0.09)
      parameter (p1=0.1402,p2=0.1285,p3=un,p4=3.15,p5=4.)
      parameter (f23=-2./3.)
C
      ANE=ELEC(ID)
      ELEC23(ID)=EXP(F23*LOG(ANE))
      ANES=EXP(SIXTH*LOG(ANE))
      ACOR=CCOR*ANES/SQRT(TEMP(ID))
      X=EXP(P4*LOG(UN+P3*ACOR))
      DWC2(ID)=P2*X
      A3=ACOR*ACOR*ACOR
      DO 10 IZZ=1,MZZ
         Z3(IZZ)=IZZ*IZZ*IZZ
         DWC1(IZZ,ID)=P1*(X+P5*(IZZ-1.)*A3)
   10 CONTINUE
      RETURN
      END