Author Topic: Oscillator strengths for triplet CC2 and singlet CIS(Dinf)  (Read 9384 times)

mpjohans

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Oscillator strengths for triplet CC2 and singlet CIS(Dinf)
« on: March 05, 2009, 09:57:14 AM »
Hello!

Should it be possible to get oscillator strengths for triplet excitations at CC2 level and/or singlet/triplet excitations at CIS(Dinf) level? TM seems to make an effort but crashes with error messages. ricc2 gets so far as to print out the "contributions of excitation levels to excited states wavefunctions as computed from the <L|R> overlap" (and the numbers), but then crashes

In the case of triplet CC2 excitations, I get the following in stderr:

PGFIO-F-253/unformatted read/unit=8/attempt to read non-existent record (direct access).
 File name = CC_XI__DEN    unformatted, direct access   record = 13
 In source file cc_sv1den.f, at line number 196

and sometimes the following in stdout:

========================
  internal module stack:
 ------------------------
    ricc2
    cc_rspdrv
    cc_rspset
 ========================

 index out of range in ilstsym!
 ricc2 ended abnormally


In the case of singlet CIS(Dinf) calcs, I get the following in stdout:

                    ========   CC DENSITY MODULE   ========

                      current wave-function model: CIS(Di)

  calculating    30 xi densities

   a semicanonical algorithm will be used

    density nr.      cpu/min        wall/min    L     R
   ------------------------------------------------------
 Fatal I/O error in CC_RDRSP:
 An error occured while opening file CCL0--1--1---0
 type,index  :L0   0
 unit number : -1
 iostat      :209

 ========================
  internal module stack:
 ------------------------
    ricc2
    cc_rspdrv
    cc_rspden
    cc_1den
    trnadb1
 ========================

  Fatal I/O error in CC_RDRSP.
 ricc2 ended abnormally


I've tried TM6-0 and TM5-10. Any help appreciated.

Have a nice day,
    Mikael J.
    http://www.iki.fi/~mpjohans


mpjohans

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Re: Oscillator strengths for triplet CC2 and singlet CIS(Dinf)
« Reply #1 on: March 05, 2009, 10:05:20 AM »
Hello again!

Forgot to insert the relevant section of my control file, which looks like:

$ricc2
  cc2
  maxiter = 400
$excitations
  irrep=b1u  multiplicity=  3  nexc= 1   npre=  0  nstart=  0
  spectrum states=all operators=diplen
  exprop states=all operators=diplen,qudlen


    MJ

christof.haettig

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Re: Oscillator strengths for triplet CC2 and singlet CIS(Dinf)
« Reply #2 on: March 27, 2009, 02:34:28 PM »
Hello,

the oscillator strength for transitions from a singlet ground state to an excited triplet state are all zero in a non-relativistic
calculation (by construction). CIS(Dinf) transition moments have not been implemented. It is of cause an error that the
program doesn't stop with a clear error message.

Christof