Example: Frequency run and transition state search¶
This example demonstrates in the first step how to calculate the Hessian, the vibrational modes and adjacent frequencies using the RunType key block for an H2 slab. The second run uses the pre-calculated Hessian and performs a transition state search along the frequency mode with the smallest frequency by using the RunType key block again.
$ADFBIN/band << eor
DefaultsConvention pre2014
Title H2 slab frequency calculation near minimum
Comment
Optimized for speed / Accuracy low
Basis very small
Demonstrates the frequencies runtype
End
KSpace 2
Accuracy 4
screening
RMadel 9
end
Dependency Basis=1e-8
RunType
Frequencies
End
GeoOpt
RestartSCF true
End
SCF
Mixing 0.2
End
Convergence
Degenerate default
End
DIIS
NCycleDamp 0
DiMix 0.5
End
Units
Length Angstrom
Angle Radian
End
ATOMS
:: TS coords
:: 0.408818 -0.059284 0.374229
:: 0.305357 0.059284 -0.374229
:: Local minimum coords:
H -0.4 0 0.1
H 0.4 0 -0.1
End
Lattice
2.645886 0 0
0 2.645886 0
End
AtomType H
DIRAC H
1 0
VALENCE
1S 1
SubEnd
BasisFunctions
1S 0.69
2P 1.25
SubEnd
FitFunctions
1S 3.16
1S 2.09
1S 1.38
2S 1.50
2P 4.00
2P 2.65
2P 1.75
3D 4.00
3D 2.50
SubEnd
End
END INPUT
eor
mv RUNKF H2SlabFreq.runkf
rm Points
Here comes the second run where the Hessian (from the frequency run) is used to find the transtition state
$ADFBIN/band << eor
DefaultsConvention pre2014
Title H2 slab TS search
Comment
Optimized for speed / Accuracy low
Basis very small
Demonstrates the GeoOpt block
End
KSpace 2
Accuracy 5.0
screening
RMadel 9
end
Dependency Basis=1e-8
RunType
TS
End
GeoOpt
Iterations 50
Converge Grad=1e-3
RestartSCF true
InitialHessian H2SlabFreq.runkf
End
SCF
Mixing 0.2
End
Convergence
Degenerate default
End
DIIS
NCycleDamp 0
DiMix 0.5
End
Units
Length Angstrom
Angle Radian
End
ATOMS
H -0.4 0 0.1
H 0.4 0 -0.1
End
Lattice
2.645886 0.000000 0.000000
0.000000 2.645886 0.000000
End
AtomType H
DIRAC H
1 0
VALENCE
1S 1
SubEnd
BasisFunctions
1S 0.69
2P 1.25
SubEnd
FitFunctions
1S 3.16
1S 2.09
1S 1.38
2S 1.50
2P 4.00
2P 2.65
2P 1.75
3D 4.00
3D 2.50
SubEnd
End
END INPUT
eor
mv RUNKF H2SlabTS.runkf
rm Points