Example: Initial Hessian

Download InitHess.run

#! /bin/sh

# In this example the Hessian from a DFTB and a MOPAC calculation is used as a
# starting guess for the Hessian in an ADF geometry optimization of Isobutane.
# This example consist of 4 calculations:
# - MOPAC frequency calculation
# - DFTB frequency calculation
# - ADF geometry optimization with initial MOPAC Hessian
# - ADF geometry optimization with initial DFTB Hessian


# ======================
# Generate MOPAC Hessian
# ======================


AMS_JOBNAME=mopac_hessian $AMSBIN/ams << eor 

Task SinglePoint

Properties
    NormalModes Yes
End

System
    Symmetrize
    Atoms 
        C      -3.01417223      -2.81892970       0.27443080
        C      -2.32560254      -1.48669854      -0.04099291
        C      -0.81033566      -1.60274167       0.15652441
        H      -2.65505660      -3.61825489      -0.40916512
        H      -4.11459952      -2.71726364       0.16084942
        H      -2.80179295      -3.12071121       1.32226630
        H      -2.71211792      -0.71788031       0.66394035
        C      -2.65045192      -1.03659727      -1.46944155
        H      -0.32255475      -0.62449394      -0.04145480
        H      -0.38172118      -2.36329425      -0.53112669
        H      -0.58228356      -1.89634208       1.20336328
        H      -2.17532684      -0.05436369      -1.67852390
        H      -3.74843413      -0.92249496      -1.59450083
        H      -2.28021380      -1.77910197      -2.20888365
    End
End

Engine Mopac
EndEngine
eor


# =======================
# Generate a dftb Hessian
# =======================


AMS_JOBNAME=dftb_hessian $AMSBIN/ams <<eor

Task SinglePoint 

Properties
   NormalModes True
End

System
    Symmetrize
    Atoms
     C      -3.014172230000      -2.818929700000       0.274430800000    
     C      -2.325602540000      -1.486698540000      -0.040992910000    
     C      -0.810335660000      -1.602741670000       0.156524410000    
     H      -2.655056600000      -3.618254890000      -0.409165120000    
     H      -4.114599520000      -2.717263640000       0.160849420000    
     H      -2.801792950000      -3.120711210000       1.322266300000    
     H      -2.712117920000      -0.717880310000       0.663940350000    
     C      -2.650451920000      -1.036597270000      -1.469441550000    
     H      -0.322554750000      -0.624493940000      -0.041454800000    
     H      -0.381721180000      -2.363294250000      -0.531126690000    
     H      -0.582283560000      -1.896342080000       1.203363280000    
     H      -2.175326840000      -0.054363690000      -1.678523900000    
     H      -3.748434130000      -0.922494960000      -1.594500830000    
     H      -2.280213800000      -1.779101970000      -2.208883650000    
    End

    Charge 0
End

Engine DFTB
    Model SCC-DFTB
    ResourcesDir DFTB.org/mio-1-1
    SCC
    End
EndEngine
eor

# Use the MOPAC Hessian generated earlier for ADF optimization

AMS_JOBNAME=adf_mopachessian "$AMSBIN/ams" <<eor
LoadSystem
   File mopac_hessian.results/ams.rkf
End
Task GeometryOptimization
GeometryOptimization
   InitialHessian
      Type FromFile
      File mopac_hessian.results/mopac.rkf
   End
End
Engine ADF
EndEngine
eor

# Use the DFTB Hessian generated earlier for ADF optimization

AMS_JOBNAME=adf_dftbhessian "$AMSBIN/ams" <<eor
LoadSystem
   File dftb_hessian.results/ams.rkf
End
Task GeometryOptimization
GeometryOptimization
   InitialHessian
      Type FromFile
      File dftb_hessian.results/dftb.rkf
   End
End
Engine ADF
EndEngine
eor