Example: Speed up SCF during geometry optimization¶

#!/bin/bash

# the System is extremely artificial but the calculation points out something useful

# The system has two CO molecules, one of which is compressed.
# We freeze the coordinates of the compressed CO molecules

# We define a gradient dependent electronic temperature (excluding the gradient of the constrained atoms)
# When far from convergence a higher value is used to ease SCF convergence (not relevant to this system)
# When the gradients become small the temperature is lowered, so that is will have negligible influence on the energy

# Here we let on purpose not converge the geometry optimization
# The final calculation should be performed as a normal single point and we explicitly set in band the ElectronicTemperature to 0.001

report=report.txt

echo "We use a gradient dependent KT value (finite electronic temperature)" > $report
printf "\nThe value of kT gets progressively lower during the optimization\n\n" >> $report
printf "\nFor two optimizers we do 3 steps and they do not converge. Yet the last single point should be done at KTlow=0.001\n\n" >> $report

for optim in Quasi-Newton FIRE
do

export AMS_JOBNAME=test.optim=$optim

rm -rf $AMS_JOBNAME.results

$AMSBIN/ams<<EOF

Log
   Debug AutomationInteractionModule
End

Task GeometryOptimization

GeometryOptimization
   Method $optim
   MaxIterations 5

   EngineAutomations
      Gradient variable=Convergence%ElectronicTemperature InitialValue=0.01 FinalValue=0.001 HighGradient=0.1 LowGradient=1.0e-3
      Iteration variable=Convergence%Criterion InitialValue=1.0e-3 FinalValue=1.0e-6 FirstIteration=0 LastIteration=1
      Iteration variable=SCF%Iterations InitialValue=1 FinalValue=300 FirstIteration=0 LastIteration=1
   End
End

Constraints
   Atom 3
   Atom 4
End

System
   Atoms
      C 0.0 0.0 0.0
      O 1.13 0.0 0.0
      C 0.0 5.0 0.0
      O 1.0 5.0 0.0
   End
End

Engine Band
   Basis Type=DZ
   Convergence
      ElectronicTemperature 0.001
      NumBoltz 100
   End
   NumericalQuality Basic
EndEngine

EOF

echo "kT series for optimizer: $optim" >> $report
grep "temperature kT" $AMS_JOBNAME.results/ams.log | awk '{print $NF}' >> $report
echo "(the last kT should be 0.001)" >> $report
echo "">>$report

echo "">>$report
echo "scf converge series for optimizer: $optim" >> $report
grep "automated value for Convergence%Criterion" $AMS_JOBNAME.results/ams.log | awk '{print $NF}' >> $report
echo "">>$report

tmp='.0'
echo "">>$report
echo "scf max Iterations series for optimizer: $optim" >> $report
echo "  (converted to a real number to be able to catch a diff)" >> $report
grep "automated value for SCF%Iterations" $AMS_JOBNAME.results/ams.log | awk '{print $NF ".0"}' >> $report
echo "">>$report

done

echo "begin report"
cat $report
echo "end report"