Scan printing unexpected energies

Questions
#1

When I run a scan with the following input:

$molecule
0 1
H1
H2 H1 0.25
$end

$rem
BASIS  =  sto-3g
GUI  =  2
JOB_TYPE  =  PES_Scan
METHOD  =  CCSD
SCF_CONVERGENCE  =  8
MAX_SCF_CYCLES = 150
GEOM_OPT_MAX_CYCLES = 300
FROZEN_SCAN = TRUE
UNRESTRICTED = FALSE
$end

$scan
stre 1 2 0.25 4.75 0.0625
$end

The end print statement Summary of potential scan prints the SCF energies and not the CCSD total energy. Is this a bug or is something in my input wrong?

Thus for one geometry the calculated energies would be:

 SCF energy                 = -0.60203845
 MP2 energy                 = -1.09344889
 CCSD correlation energy    = -0.33112566
 CCSD total energy          = -0.93316411

and it would take -0.60203845 as the energy for that geometry.

#2

I believe this is a bug. In the code, that printout is supposed to grab the energy at the target level of theory (CCSD in this case), but somehow the energy that it reads is the SCF energy. I will submit a bug ticket but you might contact Q-Chem support to see if there is a workaround. (I can’t think of an obvious one.)

#3

Thanks! Hopefully it will get solved :smiley:

#4

Further investigation suggests it’s in the coupled-cluster module. For METHOD = MP2 or RIMP2, the summary at the end is the (RI)MP2 total energy not the SCF energy.

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