Example: Initial Hessian¶
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
# ======================
"$ADFBIN/mopac.scm" << eor
PM7 GEO-OK FORCE LET NOREOR AUX(0,PRECISION=9) BONDS CHARGE=0
Coordinates generated by ADFinput (c) SCM 1998-2011
C -3.01417223 1 -2.81892970 1 0.27443080 1
C -2.32560254 1 -1.48669854 1 -0.04099291 1
C -0.81033566 1 -1.60274167 1 0.15652441 1
H -2.65505660 1 -3.61825489 1 -0.40916512 1
H -4.11459952 1 -2.71726364 1 0.16084942 1
H -2.80179295 1 -3.12071121 1 1.32226630 1
H -2.71211792 1 -0.71788031 1 0.66394035 1
C -2.65045192 1 -1.03659727 1 -1.46944155 1
H -0.32255475 1 -0.62449394 1 -0.04145480 1
H -0.38172118 1 -2.36329425 1 -0.53112669 1
H -0.58228356 1 -1.89634208 1 1.20336328 1
H -2.17532684 1 -0.05436369 1 -1.67852390 1
H -3.74843413 1 -0.92249496 1 -1.59450083 1
H -2.28021380 1 -1.77910197 1 -2.20888365 1
eor
mv results.rkf mopac.rkf
# =======================
# Generate a DFTB Hessian
# =======================
$ADFBIN/dftb << eor
Units
length Angstrom
End
System
Atoms
C -3.014172230000 -2.818929700000 0.274430800000
C -2.325602540000 -1.486698540000 -0.040992910000
C -0.810335660000 -1.602741670000 0.156524410000
H -2.655056600000 -3.618254890000 -0.409165120000
H -4.114599520000 -2.717263640000 0.160849420000
H -2.801792950000 -3.120711210000 1.322266300000
H -2.712117920000 -0.717880310000 0.663940350000
C -2.650451920000 -1.036597270000 -1.469441550000
H -0.322554750000 -0.624493940000 -0.041454800000
H -0.381721180000 -2.363294250000 -0.531126690000
H -0.582283560000 -1.896342080000 1.203363280000
H -2.175326840000 -0.054363690000 -1.678523900000
H -3.748434130000 -0.922494960000 -1.594500830000
H -2.280213800000 -1.779101970000 -2.208883650000
End
Charge 0
End
DFTB
ResourcesDir DFTB.org/mio-1-1
SCC
End
End
Task
RunType F
END
eor
# Use the MOPAC Hessian generated earlier for ADF optimization
"$ADFBIN/adf" <<eor
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
BASIS
type DZ
core Large
createoutput None
END
GEOMETRY
InitHess mopac.rkf
END
eor
# Use the DFTB Hessian generated earlier for ADF optimization
"$ADFBIN/adf" <<eor
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
BASIS
type DZ
core Large
createoutput None
END
GEOMETRY
InitHess dftb.rkf
END
eor