!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
!                                                                      !
! DIMERISATION routine                                                 !
! This routine writes reaction of a given species with a aldehyde or   !
! hydroperoxide to form a dimer                                        !                                                     !
!                                                                      !
! INPUT:                                                               !
!  - chem        : formula[a120] of the species                        !
!  - name        : code[a6] of the species fixed name                  !
!  - mass        : molar mass of the species                           !
!  - dimtype     : type od species which react which chem :            !
!                  1 to react with aldehyde, 2 with hydroperoxide      !
!                                                                      !                                                 !
! INPUT/OUTPUT                                                         !
!  - lodimer : logical to check if dimerisatyion recation was done     !
!                                                                      !
!                                                                      !
!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!!
      SUBROUTINE dimerisation(lrea,ldic,name,chem,num,mass,dimtype,
     &           lodimer)
      IMPLICIT NONE
      INCLUDE 'general.h'

! input:
      CHARACTER(LEN=lfo),INTENT(in)    :: chem
      CHARACTER(LEN=lco),INTENT(in)    :: name
      INTEGER,INTENT(in)            :: lrea,ldic
      REAL,INTENT(in)               :: mass
      INTEGER,INTENT(in)            :: dimtype

!input/output
      INTEGER,INTENT(inout)         :: num
      LOGICAL,INTENT(inout)         :: lodimer

! internal
      CHARACTER(LEN=lgr)               :: group(mca)
      INTEGER                       :: bond(mca,mca),nring,dbflg
      INTEGER                       :: i,j,k,nc,nca
      INTEGER                       :: rjg(mri,2)

      CHARACTER*1                   :: a1,a2,a3,a4
      CHARACTER(LEN=lco)               :: r(3), p(mnp)
      REAL                          :: s(mnp),ar1,ar2,ar3,f298,fratio
      INTEGER                       :: idreac, nlab
      REAL                          :: xlab,folow(3),fotroe(4)
      REAL                          :: auxinfo(9)
      CHARACTER*1                   :: charfrom,charto


! ----------
! INITIALIZE
! ----------

      nc = index(chem,' ') - 1
      CALL grbond(chem,nc,group,bond,dbflg,nring)

! IF RINGS EXIST remove ring-join characters from groups
!      IF (nring.gt.0) THEN
!        CALL rjgrm(nring,group,rjg)
!      ENDIF

      nca=0
      DO i=1,mca
        IF (group(i).EQ.' ') EXIT
        nca=nca+1
      ENDDO
 
! write the dimer species in the dictionary
!      WRITE(ldic,'(A1,A6,10X,A1,F6.1,A1)')
!     &                   'D',name,'/',mass ,'/'
      WRITE(83,*) 'dimerisation reaction for ',name,' : ',chem(1:80)
! initialize (most not used here)
      CALL rxinit3(a1,a2,a3,a4,r,s,p,ar1,ar2,ar3,
     &             f298,fratio,idreac,nlab,xlab,folow,fotroe)

! check the type of reaction
! DIM_1 for aldehyde
! DIM_2 for hydroperoxide      
      IF (dimtype.EQ.1) THEN
        r(2)= 'DIM_1'
      ELSE IF (dimtype.EQ.2) THEN
        r(2)= 'DIM_2'
      ELSE IF (dimtype.EQ.3) THEN
        r(2)= 'DIM_3'
      ELSE IF (dimtype.EQ.4) THEN
        r(2)= 'DIM_4'
      ELSE
        WRITE(6,*) 'id of the type of reaction given not possible'
      ENDIF

! ---- The species reacts with a dimtype species, if any, to form a dimer
      IF (num.GT.0) THEN
        r(1)= name
        p(1)= name
        s(1) = 1.

        ar1 = 2.78E-4
!        ar1 = 2.78E-8
        ar2 = 0.
        ar3 = 0.
        idreac=5
        charfrom='A'
        charto='D'
        CALL rxwrit_dyn(lrea,r,s,p,ar1,ar2,ar3,
     &                idreac,auxinfo,charfrom,charto)
      
!        num=num-1
        lodimer=.true.
      ENDIF
 
      RETURN

      END