!Ethylene (2/2)-CASSCF AIMS deck.
!This can be used as a template for other simulations by changing
!User options below. The deck calculates couplings for up to three
!states simultaneously coupled to the occupied state (NUMCOUP=3.0),
!which should suffice for most applications. If this needs to be increased,
!modify MPCALC accordingly.

!User options
symmetry,nosym  !Do not change!
occ,9,context=MCSCF
closed,7,context=MCSCF
wf,16,1,0
nstate=3
orient,noorient !Do not change!
geomtyp=xyz     !Do not change!
geometry={
6
ethylene ground-state geom
 C    0.0000000031    0.0000000000    0.6768496105
 C   -0.0000000013    0.0000000000   -0.6768496105
 H   -0.0000000017    0.9131426983   -1.2402810929
 H   -0.0000000095    0.9131426983    1.2402810929
 H   -0.0000000159   -0.9131426983    1.2402810929
 H    0.0000000047   -0.9131426983   -1.2402810929
}
basis=6-31g*


!Aims variables - do not change!
! FMS-Molpro does not support parallel execution.
if(NPROC_MPP.gt.1) then
skipped
endif
if(.not.modul_aims) then
skipped
endif

! tighten thresholds:
gthresh,twoint=1.0d-13
gthresh,energy=1.0d-7,gradient=1.0d-2
! records used by AIMS
orbrec=2101.2
cirec=2501.2
diabrec=3000.2
gradrec0=5101.1
do icoup=1,nstate-1
  gradrec(icoup)=gradrec0+icoup
enddo

MPINIT={ !Find the initial CASSCF wavefunction
if(orbital.eq.0) then
  hf
  multi
  pspace,10.0
  wf;state,nstate
  maxiter,20
  orbital,orbrec
  ciguess,cirec
  save,det=cirec
  if (status.lt.0) then
    text, MCSCF failed in MPINIT.
    text, Attempting uncoupled iterations.
    {multi,so
    pspace,10.0
    wf;state,nstate
    orbital,orbrec
    ciguess,cirec
    save,det=cirec
    maxiter,50}
  endif
  if(status.lt.0) then
    text,ERROR: could not converge MCSCF.
    text,FMS should now stop
    STOP
  endif
endif
}

MPCALC={ !Calculate Energy and Forces
if (jtrj.eq.0) then
  show,itimestep,itrj;
else
  show,itimestep,itrj,jtraj
endif
data,truncate,diabrec
data,truncate,gradrec0
do icoup=1,nstate-1
  data,truncate,gradrec(icoup)
enddo
data,copy, orbrec, diabrec
{multi
pspace,10.0
wf;state,nstate
maxiter,20
orbital,orbrec
ciguess,cirec
dm,orbrec
save,det=cirec
diab,diabrec,save=orbrec
}
if (status.lt.0) then
  text, MCSCF failed in MPCALC.
  text, Attempting uncoupled iterations.
  {multi
  pspace,10.0
  state,nstate
  orbital,orbrec
  ciguess,cirec
  dm,orbrec
  save,det=cirec
  {iterations
    do,uncouple,1,to,10}
  maxiter,30
  diab,diabrec,save=orbrec
  }
endif
if(status.lt.0) then
  text,ERROR: could not converge MCSCF.
  text,FMS should now stop
  STOP
endif
do istate=1,nstate
  ener( istate )=energy( istate )
enddo
pop;density,orbrec,state=stateind
if (numcoup.eq.0.0) then
  {multi
  pspace,10.0
  wf;state,nstate
  maxiter,20
  orbital,orbrec
  ciguess,cirec
  save,det=cirec
  diab,diabrec,save=orbrec
  cpmcscf,grad,stateind,save=gradrec0;
  }
elseif (numcoup.eq.1.0) then
  {multi
  pspace,10.0
  wf;state,nstate
  maxiter,20
  orbital,orbrec
  ciguess,cirec
  save,det=cirec
  diab,diabrec,save=orbrec
  cpmcscf,grad,stateind,save=gradrec0;
  cpmcscf,nacm,stateind,stateind2(1),save=gradrec(1);
  }
elseif (numcoup.eq.2.0) then
  {multi
  pspace,10.0
  wf;state,nstate
  maxiter,20
  orbital,orbrec
  ciguess,cirec
  save,det=cirec
  diab,diabrec,save=orbrec
  cpmcscf,grad,stateind,save=gradrec0;
  cpmcscf,nacm,stateind,stateind2(1),save=gradrec(1);
  cpmcscf,nacm,stateind,stateind2(2),save=gradrec(2);
  }
elseif (numcoup.eq.3.0) then
  {multi
  pspace,10.0
  wf;state,nstate
  maxiter,20
  orbital,orbrec
  ciguess,cirec
  save,det=cirec
  diab,diabrec,save=orbrec
  cpmcscf,grad,stateind,save=gradrec0;
  cpmcscf,nacm,stateind,stateind2(1),save=gradrec(1);
  cpmcscf,nacm,stateind,stateind2(2),save=gradrec(2);
  cpmcscf,nacm,stateind,stateind2(3),save=gradrec(3);
  }
elseif (numcoup.ge.4.0) then
  text, Number of couplings requested: $numcoup beyond limits of input deck.
  text, Please modify input deck accordingly.
  STOP
endif
forces;samc,gradrec0
}

MGCOUP={
forces;nacm,gradrec(ncoup)
}

! writes a molden file
WRITEMOLDEN={
moldenfile='$itrj.$itimestep.molf'
put,molden,$moldenfile;
}

AIMS,dir='./aims_ethyl_CASSCF'