ccsd(t) optimization for molecules containing atoms below the 3rd row of the PT
ghoffman at edinboro.edu
Mon Jul 21 19:31:29 BST 2003
I have been trying to calculate vibrational frequencies for krypton difluoride at the level of CCSD(T) with no success. The error message given by the program (during optg) is given below; everything before this point works as expected. After playing around with the optg command, I discovered that the CCSD(T) calculation will work if all atoms in the molecule are from the first three rows of the periodic table. Similarly, the calculation works for krypton difuoride if it is performed at the level of HF. Clearly, the absence of a model Hessian for atoms below the third row (Kr in this case) is a problem, but only for high-level calculations such as CCSD(T) or CI (I also tried CI).
So, is it possible to perform an optimization and vibrational frequency calculation at the level of CCSD(T) (or CI) for a molecule containing one or more atoms below the third row of the periodic table? If so, what are the necessary commands or options that must be given?
Thank you for your help.
STARTING GEOMETRY OPTIMIZATION FOR CCSD(T)
CONVERGENCE THRESHOLDS: 0.300E-03 (STEP) 0.300E-03 (GRADIENT) 0.100E-05 (ENERGY)
MAX. NUMBER OF STEPS: 50
*** Long output written to logfile /scratch-huldra/LSBATCH/908128.19Jun2003134623/krf2smccvib.log ***
Sorry, Model Hessian not yet available for KR
Incrementing variable KRX1 by +/- 0.010 BOHR
Permutation not found: symmetry= 1 i= 6 label=2px
bflab: 13d0 13d2+ 13d0 13d2+ 13d0 13d2+ 13d0 13d2+ 15g0 15g4\
+ 21s 21s 21s 21s 21s 21s 21s 21s 21s 21s 21s 21s 21s 21s 22pz \
22pz 22pz 22pz 22pz 22pz 22pz 23d0 23d2+ 23d0 23d2+ 23d0 23d2+ 23d0 23d2+ 23d0 23d2\
24f2+ 24f0 24f2+ 24f0 24f2+ 25g0 25g4+ 25g2+ 25g0 25g4+ 25g2+
GA ERROR termxy
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