                  V I B R M T (diatomic codes only)

      VIBRMT sets up channel and R-matrix data needed for a non-adiabatic
      treatment of nuclear motion.  It takes pre-procesed data from INTERF
      then outputs new channel and R-matrix files for input to RSOLVE

      Input files:
        Channel and target data          (on unit LUCHAN)
        Fixed nuclei R-matrix data       (on unit LURMT )

      Output files:
        Vibration and dissociation channel data  (on unit LUVCHN)
        Non-adiabatic R-matrix data              (on unit LUNRMT)


      The following PARAMETERs are used to define array dimensions

      MAXFCH =100  maximum number of fixed nuclei scattering channels
      MAXTGT = 20  maximum number of target electronic states
      MAXPTS = 30  maximum number of geometries
      MAXPOL = 20  maximum number of non-adiabatic R-matrix poles
                   
      The main data describing the run is input via namelist /VRMTIN/.
      Additional input will be required by routine VIBINI, to describe 
      the vibrational states of the target (and optionally, by routine 
      DISINI, to describe dissociating states).  For further details
      see below.

      Namelist input /VRMTIN/

        The format of the following is 
       (Name, Type, Dimension, Default, Limits, ! description)
        Unless specified otherwise, the default value applies to all elements
        of array variables.
        

        BBLOCH   R   1          0.    [:]
           ! Coefficient in electronic Bloch operator

        BIGB     R   1          0.    [:]
           ! Coefficient in nuclear Bloch operator

        GUTOT    I   1          0     [-1:1]     
           ! G/U symmetry of total system

        ICFORM   C   1         'U'   ['U'|'F']
           ! format flag for channel dataset, 'F' for formatted, 'U' for
             unformatted

        ICROSS   I  (2,NCROSS)       [1:NPOLE-1],[1:NGEOM-1]
           ! for each pair of diabatic crossings I,
             ICROSS(1,I) = label of (initially) lower pole
             ICROSS(2,I) = label of geometry immediately preceding the crossing

        ICUP     I  (2,NCUPP)        [1:NPOLE-1],[2:NPOLE]
           ! for each set of coupled poles I,
                 ICUP(1,I) = label of lowest member of set
                 ICUP(2,I) = label of highest member
                 (these must be ordered by increasing pole label not geometry)

        IGREF    I   1          1    [1:NGEOM]
            ! Label of reference geometry for diabatic transformation of 
              coupled electronic states. The chosen geometry should if
              possible, be well away from any avoided curve crossings.

        INRFRM   C   1         'U'   ['U'|'F']
           ! Formatted/unformatted switch for unit LUNRMT

        IPRNT    I   6          0    [0|1]
           ! Debug print switches :
             In each case -1 gives less than the default output and +1
             more than the default
                 (1) =1 Print all input data
                 (2) =1 Print transformed CI data
                 (3) =1 Print vibrational wavefunction data
                 (4)  Used by nuclear motion code
                 (5)  Used by nuclear motion code
                 (6) =1 Print all output data

        IRFORM   C   1         'U'   ('U'|'F')
           ! format flag for R-matrix dataset, 'F' for formatted, 'U' for
             unformatted

        ISMAX    I   1          0    [0:]        
           ! maximum multipole to be used in the expansion of the
             long range potentials (note that if either ALPHA0 or ALPHA2
             is non-zero then ISMAX must be at least 3)

        IVCFRM   C   1         'U'   ['U'|'F']
           ! Formatted/unformatted switch for unit LUVCHN

        IWRITE   I   1          6    [1:]        
           ! logical unit for printed output

        LUCHAN   I   1         10    [1:]        
           ! logical unit for input channel and target datasets

        LUNRMT   I   1         29     [1:]
           ! Logical unit holding non adiabatic R-matrix data

        LURMT    I   1         21    [1:]
           ! logical unit holding input R-matrix poles and amplitudes
             together with multipole expansion of asymptotic potentials,
             and parameterized Buttle corrections 

        LUVCHN   I  1          28    [1:]
           ! Logical unit holding vibrational/dissociating
             channel data

        MGVN     I   1               [0:]
           ! total symmetry of system

        NAME     C   60                          
           ! title for any output

        NCHSET    I   1          1    [0:]        
           ! set numbers of required channel dataset(s)

        NBASIS    I   1          25   [0:]
           ! number of Legendre polynomials to be used in expansion
             of nuclear motion hamiltonian

        NBIGSET   I   1          1    [1:NGEOM]
           ! Sequence number, within NRMSET, of case having largest NOCSF
            
        NCREF     I   1          1    [1:NGEOM]
           ! Label of some geometry unaffected by crossings (this may be
             the same as IGREF)

        NDIS      I   1          0    [0:NPOLE]
           ! number of dissociating channels

        NGEOM     I   1          1    [1:]
           ! number of target geometries

        NNRSET    I   1          1    [1:]
           ! Set number for input non-adiabatic R-matrix data

        NPOLE    I   1          0    [0:]        
           ! number of R-matrix poles which are to be treated non-adiabatically
             (This must not exceed the value of NPOLE set in INTERF)

        NRMSET    I   1          1    [0:]
           ! set number of required R-matrix dataset(s)

        NRQUAD    I   1        201    [1:]
           ! number of quadrature points for integrals in adiabatic
             approximation ( if =0 then code decides)

        NVCSET    I   1          1    [1:]
           ! Set number for input vibrational/dissociating channel
             data

        NVTARG    I MAXTGT       1    [1:]
           ! number of vibrational levels for each target state

        R         R   NGEOM           [0.:]        
           ! internuclear separations

        STOT      I   1               [1:]        
           ! spin multiplicity of total system
