Firefly and PC GAMESS-related discussion club


 
Learn how to ask questions correctly  
 
 
We are NATO-free zone
 



Abort in MP2 gradients

Slawomir Janicki
slawomir.janicki@comcast.net


I got an abort in MP2 gradient:

Smallest alpha-alpha delta epsilon is:   0.32335906


------------------------------------   ------------------------------------
ADVANCED RHF-MP2 PROPERTIES/GRADIENT   PROGRAM WRITTEN BY ALEX A. GRANOVSKY
------------------------------------   ------------------------------------
MP2 TRANSFORMATION CANNOT ASSIGN A DEFINITE ORBITAL SYMMETRY TO MO   56
JOB ABORTS.  YOU MUST EITHER
 A) PROVIDE A SYMMETRY ADAPTED MO SET BY GUESS=MOREAD
 B) ENTER NOSYM=1 TO USE THESE SYMMETRY BROKEN MO-S.

ADDRESS 0x00664F46 HAS INITIATED PROGRAM ABORT BECAUSE OF FATAL ERROR(S)

What parameters are the most likely culprits?
The relevant lines from the input file are:

$CONTRL INTTYP=HONDO ICUT=13 WIDE=.T. $END
$SYSTEM TIMLIM=5000000 MWORDS=200 KDIAG=0 NOJAC=30 NP=1 $END
$CONTRL MPLEVL=2 $END
$SCF NCONV=9 $END
$MP2 METHOD=1 $END
$MP2GRD TOL1=1D-18 TOL2=1D-18 $END
$STATPT METHOD=NR NSTEP=100 OPTTOL=1E-6 TRMIN=1E-6 $END

The basis set in this calculation is aug-cc-pCVTZ. The error occurred in step 15 of geometry optimization and the gradients were a bit iffy:

         MAXIMUM GRADIENT =  0.0000051    RMS GRADIENT = 0.0000019
         SKIPPING HESSIAN UPDATE...
            ACTUAL ENERGY CHANGE WAS   0.0000000002
         PREDICTED ENERGY CHANGE WAS  -0.0000000007 RATIO= -0.291
              NR STEP HAS LENGTH         =   0.000090
         RADIUS OF STEP TAKEN=   0.00009  CURRENT TRUST RADIUS=   0.30000


In a previous calculations the geometry would not converge with the aug-cc-pCVDZ basis set if any of NCONV ICUT TOL1 TOL2 we less tight.

Slawomir


[ Previous ] [ Next ] [ Index ]           Thu Dec 5 '13 2:52am
[ Reply ] [ Edit ] [ Delete ]           This message read 593 times