I'm trying to run some simple QM calculations using GAMESS, but it seems to give a wrong result. The expected value of total energy is -24.258337146 a.u. while GAMESS returns 490.9315519299. I'm pretty much sure that the problem is in how i set up the calculation. Studied system comprises 64 Hydrogen atoms arranged in cubic structure. The parameters are:
$contrl runtyp=energy scftyp=rhf maxit=50 $end
$basis gbasis=STO ngauss=3 $end
$scf dirscf=.t. diis=.true. ethrsh=1.0 swdiis=0.0 damp=.t. $end
$data
Hydrogen cube HF single point energy calculation
C1
H 1 0.000000 0.000000 0.000000
#Coordinates of 63 remaining Hydrogen atoms
$end
Simply
! File created by MacMolPlt 7.4
$CONTRL SCFTYP=RHF RUNTYP=ENERGY MAXIT=50 MULT=1
NOSYM=0 $END
$SYSTEM TIMLIM=525600 MEMORY=1000000 $END
$BASIS GBASIS=MINI $END
$SCF DIRSCF=.TRUE. VTSCAL=.FALSE. $END
$DATA
Hydrogen cube HF single point energy calculation
OH
H 1.0 0.45000 0.45000 0.45000
H 1.0 1.35000 0.45000 0.45000
H 1.0 1.35000 1.35000 0.45000
H 1.0 1.35000 1.35000 1.35000
$END
from output with VTSCAL=.FALSE.
in Oh symmetry NOSYM=0
TOTAL ENERGY = -24.2583347907
VIRIAL RATIO (V/T) = 1.3845939898 !!!!!
with VTSCAL =.TRUE. in $SCF (For more information on this option, which is most useful during a geometry search, see M.Lehd and F.Jensen, J.Comput.Chem. 12, 1089-1096(1991)
TOTAL ENERGY = -24.57410398 in Oh symmetry (NOSYM=0)
Hello,
The structure was optimized before single point calculation?
Structure has not been optimized, but is has been tested using other softwares without any problems.
Simply
! File created by MacMolPlt 7.4
$CONTRL SCFTYP=RHF RUNTYP=ENERGY MAXIT=50 MULT=1
NOSYM=0 $END
$SYSTEM TIMLIM=525600 MEMORY=1000000 $END
$BASIS GBASIS=MINI $END
$SCF DIRSCF=.TRUE. VTSCAL=.FALSE. $END
$DATA
Hydrogen cube HF single point energy calculation
OH
H 1.0 0.45000 0.45000 0.45000
H 1.0 1.35000 0.45000 0.45000
H 1.0 1.35000 1.35000 0.45000
H 1.0 1.35000 1.35000 1.35000
$END
from output with VTSCAL=.FALSE.
in Oh symmetry NOSYM=0
TOTAL ENERGY = -24.2583347907
VIRIAL RATIO (V/T) = 1.3845939898 !!!!!
with VTSCAL =.TRUE. in $SCF (For more information on this option, which is most useful during a geometry search, see M.Lehd and F.Jensen, J.Comput.Chem. 12, 1089-1096(1991)
TOTAL ENERGY = -24.57410398 in Oh symmetry (NOSYM=0)
This tutorial might be of help: Tutorial on Density Functional Theory using GAMESS
https://medium.com/modern-physics/tutorial-on-density-functional-theory-using-gamess-5c3e988f5f01
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