Molcas Forum

lwang

Member

Registered: 2024-10-14

Posts: 16

The input optimization problem of s0 / s1 conic intersection point

Dear all:
       I recently used openmolcas to optimize the first excited state of thymine ( i.e., root 2 ) in pcm water solvent, and he had root 1 and root 2 flipping problems. So I took the flip structure to optimize the cone intersection of s0 / s1. My input is as follows, please help me to see if it is correct to optimize the conical intersection.
       

      &GATEWAY
coord =t.xyz
 basis =Aug-cc-pvdz
 group = C1
 RF-input
 PCM-model; solvent= water
 End of RF-input
  Constraints
     a = Ediff 1 2
    Value
     a = 0.000
  End of Constraints
>>> EXPORT MOLCAS_MAXITER = 500
>>> DO WHILE
&SEWARD
    DoAnalytical
&RASSCF
   Charge =-1
   spin=2
   nActEl=13 0 0
   Ras2=12
   ciroot =8 8 1
   Rlxroot=1
   RFROot=1
&MCLR
  ITERations=500
  THREshold =4.0e-3
&SLAPAF
  Thrshld = 5.0D-6 1.0D-3
>>> END DO

Ignacio

Administrator

From: Uppsala

Registered: 2015-11-03

Posts: 1,203

Re: The input optimization problem of s0 / s1 conic intersection point

It looks OK at first sight, but I'm not it will work with PCM. In any case, the meaning of a root-specific reaction field is debatable at a conical intersection.