Examples

These examples show how to run Quantum ESPRESSO through the AMS driver.

  • All examples can be run from the command-line and most of them are also available in $AMSHOME/examples/QE

  • Most of the examples can also be copy-pasted or opened directly in the AMSinput GUI

Important

These examples do not necessarily contain scientifically good settings!

Typically you should increase the energy cutoff and k-point sampling for scientifically good results.

See also

Single-Point Calculation + Band Structure

Input File (run from command-line or the AMSinput GUI)
#!/bin/sh

export SCM_DISABLE_MPI=1  # must be set when using the Quantum ESPRESSO engine, see documentation

"$AMSBIN/ams" --delete-old-results << EOF
Task SinglePoint

System
    Atoms
        Si      -0.67520366      -0.67520366      -0.67520366
        Si       0.67520366       0.67520366       0.67520366
    End
    Lattice
        0.00000000       2.70081465       2.70081465
        2.70081465       0.00000000       2.70081465
        2.70081465       2.70081465       0.00000000
    End
End

Engine QuantumEspresso
    System
       ecutwfc 50
       ecutrho 400
       occupations smearing
       degauss 0.001
    End
    K_Points automatic
        5 5 5 0 0 0
    End
    Pseudopotentials
        Family pslibrary-US
        Functional PBE
    End
    Properties
        BandStructure Yes
    End
EndEngine
EOF

  • Single-point calculation for bulk silicon using a regular Monkhorst-Pack k-point grid.

  • The electronic band structure is calculated along high-symmetry lines in the Brillouin zone.

  • You can view the resulting band structure with the program $AMSBIN/amsbands.

_images/BandStructureStandardPath.png

Lattice Optimization of Silicon

Input File (run from command-line or the AMSinput GUI)
#!/bin/sh

export SCM_DISABLE_MPI=1  # required for Quantum ESPRESSO - see documentation

#============================================================================
# Example showing how to run a lattice optimization with Quantum ESPRESSO.
#
# This example is also available as a tutorial using the 
# graphical user interface
#
# Important: always use carefully converged k-points and energy cutoffs
# for lattice optimizations! 
#
# You may want to symmetrize the optimized structure using the "star"
# button in AMSinput.
#============================================================================

"$AMSBIN/ams" --delete-old-results <<EOF
Task GeometryOptimization

GeometryOptimization
    OptimizeLattice Yes
End

System
    Atoms
        Si      -0.67875000      -0.67875000      -0.67875000
        Si       0.67875000       0.67875000       0.67875000
    End
    Lattice
        0.0 3.0 3.0
        3.0 0.0 3.0
        3.0 3.0 0.0
    End
End

Engine QuantumEspresso
    K_Points automatic
        10 10 10 0 0 0
    End
    Pseudopotentials
        Family SSSP-Efficiency
        Functional PBE
    End
    System
        ecutwfc 40.0
        ecutrho 320.0
        occupations Fixed
    End
EndEngine
EOF

  • Full structural optimization of bulk silicon

  • Both the atomic positions and lattice parameters are relaxed

_images/LatticeOptimization.png

DFT+U (Hubbard U) Calculation for Anti-ferromagnetic FeO

Input File (run from command-line or the AMSinput GUI)
#!/bin/sh

# Run AMS driver without MPI, so that QE can be MPI parallel.
export SCM_DISABLE_MPI=1

"$AMSBIN/ams" --delete-old-results << EOF

Task SinglePoint

System
    Atoms
        Fe  0.0    0.0    0.0   QE.Label=Fe1
        Fe  2.165  2.165  0.0   QE.Label=Fe2
        O   0.0    2.165  0.0
        O   2.165  0.0    0.0
    End
    Lattice
        4.33   0.0   0.0
        0.0    4.33  0.0
        2.165  0.0   2.165
    End
End

Engine QuantumEspresso
   System
       ecutwfc 40.0
       ecutrho 160.0
       occupations smearing
       smearing mv
       degauss 0.02
       nspin 2
       starting_magnetization label=Fe1 value=0.5
       starting_magnetization label=Fe2 value=-0.5
   End
   Pseudopotentials
      Family pslibrary-PAW
      Functional PBEsol
   End
   K_Points automatic
      5 5 5 0 0 0
   End
   Hubbard ortho-atomic
      U Fe1-3d 4.6
      U Fe2-3d 4.6
   End
EndEngine

EOF

  • DFT+U calculation for antiferromagnetic FeO

  • The QE.Label= keyword is employed to define distinct Fe species

  • The starting_magnetization keyword refers to the labels to give different initial spin magnetizations, leading to an anti-ferromagnetic solution.

  • Hubbard U is specified in the new Quantum ESPRESSO 7.1 format

_images/HubbardU_SpinPolarized_Antiferromagnetic.png

Pseudopotential Selection

Command-line runscript
#!/bin/sh

export SCM_DISABLE_MPI=1  # required for engine Quantum ESPRESSO, see documentation


# =======================================================================================
# Example illustrating various ways of selecting Pseudopotentials with the QE engine.
# =======================================================================================
#
# All jobs run into this example should give the exact same result, 
# as they are using the same PPs.
# All that differs is the way that the PPs were selected.


# Make a folder with "custom" PP files to test with:
#
# We will use the SG15 pseudopotentials directory that comes 
# with the AMS QE package as an example.
# You could use any other directory with .upf files ...
PPDIR="$("$AMSBIN/amspackages" loc qe)/upf_files/GGA/PBE/SR/SG15-1.2/UPFs"

# Make a custom directory containing files named element.upf:
mkdir -p my_pp_directory
cp "$PPDIR"/C_ONCV_PBE-1.2.upf my_pp_directory/C.upf  # rename to element.upf
cp "$PPDIR"/H_ONCV_PBE-1.2.upf my_pp_directory/H.upf  # rename to element.upf

# If using special QE labels, the file name should be label.upf:
cp "$PPDIR"/H_ONCV_PBE-1.2.upf my_pp_directory/H1.upf

# Get an absolute path to the directory the jobs starts in:
if test "$OS" = "Windows_NT"; then
    # Absolute paths should be Windows style (with drive letters like C:)
    STARTDIR=$(pwd -W)
else
    STARTDIR=$(pwd)
fi


# Make a system to test with:
echo "
    System
        Atoms
            C 0.9685 1.9663  0.0000
            H 1.6614 2.2162  0.7898
            H 0.0162 1.6927  0.4297
            H 0.8388 2.8201 -0.6485
            H 1.3576 1.1363 -0.5710 QE.Label=H1
        End
        Lattice
            5.0 0.0 0.0
            0.0 5.0 0.0
            0.0 0.0 5.0
        End
    End
" > system.in


# Option 1: Pseudopotentials%Family
# ---------------------------------
#
# The easiest way is to just use the Pseudopotentials%Family key and 
# let the engine figure out which PPs to use.

AMS_JOBNAME=1_family "$AMSBIN/ams" << EOF
    Task SinglePoint
    @include system.in

    Engine QuantumEspresso
        Pseudopotentials
            Family SG15
            Functional PBE
        End
        K_points Gamma
        End
    EndEngine
EOF


# Option 2: Pseudopotentials%Directory
# ------------------------------------
#
# Specifies a path to a directory with PP files named element.upf or label.upf.
# The path to the directory can be absolute or relative.

AMS_JOBNAME=2a_directory_relpath "$AMSBIN/ams" << EOF
    Task SinglePoint
    @include system.in

    Engine QuantumEspresso
        Pseudopotentials
            Directory my_pp_directory
        End
        K_points Gamma
        End
    EndEngine
EOF

AMS_JOBNAME=2b_directory_abspath "$AMSBIN/ams" << EOF
    Task SinglePoint

    System
        Atoms
            C 0.9685 1.9663  0.0000 QE.Label=C1  # no PP file for C1 in folder, fallback to C
            H 1.6614 2.2162  0.7898
            H 0.0162 1.6927  0.4297
            H 0.8388 2.8201 -0.6485
            H 1.3576 1.1363 -0.5710 QE.Label=H1
        End
        Lattice
            5.0 0.0 0.0
            0.0 5.0 0.0
            0.0 0.0 5.0
        End
    End

    Engine QuantumEspresso
        Pseudopotentials
            Directory $STARTDIR/my_pp_directory
        End
        K_points Gamma
        End
    EndEngine
EOF


# Option 3: Pseudopotentials%Files
# ------------------------------------
#
# Individually specify paths to files for each element or label.

# By default relative paths are relative to the root of the 
# PP library installed via AMSpackages.

AMS_JOBNAME=3a_files_relpath "$AMSBIN/ams" << EOF
    Task SinglePoint
    @include system.in

    Engine QuantumEspresso
        Pseudopotentials
            Files Label=C  Path=GGA/PBE/SR/SG15-1.2/UPFs/C_ONCV_PBE-1.2.upf
            Files Label=H  Path=GGA/PBE/SR/SG15-1.2/UPFs/H_ONCV_PBE-1.2.upf
            Files Label=H1 Path=GGA/PBE/SR/SG15-1.2/UPFs/H_ONCV_PBE-1.2.upf
        End
        K_points Gamma
        End
    EndEngine
EOF

# Paths relative to the starting directory of AMS should be prefixed with "./".

AMS_JOBNAME=3b_files_exrelpath "$AMSBIN/ams" << EOF
    Task SinglePoint
    @include system.in

    Engine QuantumEspresso
        Pseudopotentials
            Files Label=C  Path=./my_pp_directory/C.upf
            Files Label=H  Path=./my_pp_directory/H.upf
            Files Label=H1 Path=./my_pp_directory/H1.upf
        End
        K_points Gamma
        End
    EndEngine
EOF

# Absolute paths are also supported.

AMS_JOBNAME=3c_files_abspath "$AMSBIN/ams" << EOF
    Task SinglePoint
    @include system.in

    Engine QuantumEspresso
        Pseudopotentials
            Files Label=C  Path="$STARTDIR/my_pp_directory/C.upf"
            Files Label=H  Path="$STARTDIR/my_pp_directory/H.upf"
            Files Label=H1 Path="$STARTDIR/my_pp_directory/H1.upf"
        End
        K_points Gamma
        End
    EndEngine
EOF

# Combinations between absolute, relative and explicit relative paths also work.

AMS_JOBNAME=3d_files_mixed "$AMSBIN/ams" << EOF
    Task SinglePoint
    @include system.in

    Engine QuantumEspresso
        Pseudopotentials
            Files Label=C  Path=GGA/PBE/SR/SG15-1.2/UPFs/C_ONCV_PBE-1.2.upf
            Files Label=H  Path=./my_pp_directory/H.upf
            Files Label=H1 Path="$STARTDIR/my_pp_directory/H1.upf"
        End
        K_points Gamma
        End
    EndEngine
EOF

This example illustrates various methods for selecting pseudopotentials. It covers:

  • Pseudopotentials%Family: Predefined sets for simple selection.

  • Pseudopotentials%Directory: Directory containing files H.upf, He.upf, etc.

  • Pseudopotentials%Files: Specify each individual pseudopotential file (similar to standalone Quantum ESPRESSO).

All these options are also accessible from the AMSinput GUI.

_images/PseudopotentialSelection.png

Slab With Dipole Correction, Work Function

Input File (run from command-line or the AMSinput GUI)
#!/bin/sh

export SCM_DISABLE_MPI=1
export AMS_JOBNAME=DipoleCorrection_WorkFunction

#============================================================================
# Example showing how to apply a dipole correction for a slab system.
# This gives two separate vacuum levels on the different sides of the slab.
# The respective work functions are calculated as differences
# between the vacuum levels and the Fermi energy.
#
# This example uses internally the pp.x and average.x utilities from Quantum
# ESPRESSO to get the plane-averaged electrostatic potential.
#
# For details about the input to pp.x, and average.x, see:
#  - https://www.quantum-espresso.org/Doc/INPUT_PP.html
#  - https://gitlab.com/QEF/q-e/-/blob/qe-7.1/PP/src/average.f90
#
# This example is based on the work function tutorial for BAND and the
# work function example in Quantum ESPRESSO (PP/examples/WorkFct_example).
#
# Better-converged numbers can be obtained by increasing the k-space
# sampling and energy cutoff.
#============================================================================

"$AMSBIN/ams" --delete-old-results <<EOF
Task SinglePoint

System
    Atoms
        Al 1.4319 1.4319 8.925
        Al 0.0000 0.0000 10.95
        Al 1.4319 1.4319 12.975
        Al 0.0000 0.0000 15
        F 0.0000 0.0000 18.27
        Li 1.4319 1.4319 18.27
        F 1.4319 1.4319 20.295
        Li 0.0000 0.0000 20.295
    End
    Lattice
       2.86378246       0.00000000       0.00000000
       0.00000000       2.86378246       0.00000000
       0.0 0.0 30.0
    End
End

Engine QuantumEspresso
    K_Points automatic
        2 2 1 1 1 1
    End
    Pseudopotentials
        Family GBRV
        Functional PBE
    End
    System
        ecutwfc 40.0
        occupations smearing
        smearing gaussian
        degauss 0.02
        edir 3
        emaxpos 0.90
        eopreg 0.10
    End
    Electrons
        conv_thr 1.0e-10
    End
    Control
        tefield Yes
        dipfield Yes
    End
    Properties
        WorkFunction Yes
    End
EndEngine
EOF

$AMSBIN/amspython -c '
import scm.plams
import matplotlib.pyplot as plt

job = scm.plams.AMSJob.load_external("'$AMS_JOBNAME'.results/ams.rkf")

wf_results = job.results.get_work_function_results( "eV", "Angstrom" )
ax = scm.plams.plot_work_function(*wf_results)

ax.set_title("Electrostatic Potential Profile", fontsize=14)
ax.set_xlabel("Shifted coordinate (angstrom)", fontsize=13)
ax.set_ylabel("Electrostatic potential (eV)", fontsize=13)

plt.savefig("work_function.png")
'

  • Recommended: Place the system in the middle of the unit cell to calculate the work function.

  • Apply a dipole correction to account for the dipole moment across the vacuum between periodic images

  • This gives two separate vacuum levels on the different sides of the slab

  • The work functions are calculated as the difference between the vacuum level and the Fermi energy.

_images/DipoleCorrection_WorkFunction.png

Numerical Calculation of Phonons

Input File (run from command-line or the AMSinput GUI)
#!/bin/sh

export SCM_DISABLE_MPI=1

AMS_JOBNAME=DiamondNumericalPhonons_Curtarolo "$AMSBIN/ams" --delete-old-results << EOF
Task SinglePoint

System
    Atoms
        C    -0.44625000    -0.44625000    -0.44625000
        C     0.44625000     0.44625000     0.44625000
    End
    Lattice
         0.00000000     1.78500000     1.78500000
         1.78500000     0.00000000     1.78500000
         1.78500000     1.78500000     0.00000000
    End
End

Properties
    Phonons Yes
End

Phonons
    Method Numerical
End

NumericalPhonons
    SuperCell
        2 0 0
        0 2 0
        0 0 2
    End
    AutomaticBZPath Yes
End

Engine QuantumEspresso
    K_Points automatic
        3 3 3 0 0 0
    End
EndEngine

EOF

# This section uses PLAMS to plot the phonons bands in a Python environment
AMS_JOBNAME=DiamondNumericalPhonons_Curtarolo $AMSBIN/amspython -c '
import os
import scm.plams
import matplotlib.pyplot as plt

results_file = os.environ["AMS_JOBNAME"]+".results/ams.rkf"
job = scm.plams.AMSJob.load_external(results_file)

phonons_data = job.results.get_phonons_band_structure(unit="cm^-1")
ax = scm.plams.plot_phonons_band_structure(*phonons_data)
ax.set_ylabel("$E$ (cm$^{-1}$)")
ax.set_xlabel("Path")
ax.set_title("Diamond Phonons")
plt.savefig("phonons.png")

properties_data = job.results.get_phonons_thermodynamic_properties( properties_unit=["kJ/mol", "J/K/mol"] )
ax = scm.plams.plot_phonons_thermodynamic_properties(*properties_data)
ax.set_ylabel("Thermodynamic Properties")
ax.set_xlabel("Temperature (K)")
plt.savefig("thermodynamics.png")
'

  • Calculate phonon dispersion curves of diamond using numerical differentiation.

  • The dynamical matrix is constructed within the supercell approximation by computing forces resulting from finite atomic displacements.

  • Visualize the results with the AMSbands GUI or the Python PLAMS library.

_images/DiamondNumericalPhonons.png

Analytical Calculation of Phonons Using DFPT

Input File (run from command-line or the AMSinput GUI)
#!/bin/sh

export SCM_DISABLE_MPI=1

AMS_JOBNAME=DiamondPhonons_Curtarolo "$AMSBIN/ams" --delete-old-results << EOF
Task SinglePoint

System
    Atoms
        C    -0.44625000    -0.44625000    -0.44625000
        C     0.44625000     0.44625000     0.44625000
    End
    Lattice
         0.00000000     1.78500000     1.78500000
         1.78500000     0.00000000     1.78500000
         1.78500000     1.78500000     0.00000000
    End
End

Properties
    Phonons Yes
End

Engine QuantumEspresso
    K_Points automatic
        3 3 3 0 0 0
    End
    Phonons
        asr crystal
        Q_Points automatic
           4 4 4 0 0 0
        End
    End
EndEngine

EOF

# This section uses PLAMS to plot the phonons bands in a Python environment
AMS_JOBNAME=DiamondPhonons_Curtarolo $AMSBIN/amspython -c '
import os
import scm.plams
import matplotlib.pyplot as plt

results_file = os.environ["AMS_JOBNAME"]+".results/ams.rkf"
job = scm.plams.AMSJob.load_external(results_file)

phonons_data = job.results.get_phonons_band_structure(unit="cm^-1")
ax = scm.plams.plot_phonons_band_structure(*phonons_data)
ax.set_ylabel("$E$ (cm$^{-1}$)")
ax.set_xlabel("Path")
ax.set_title("Diamond Phonons")
plt.savefig("phonons.png")

properties_data = job.results.get_phonons_thermodynamic_properties( properties_unit=["kJ/mol", "J/K/mol"] )
ax = scm.plams.plot_phonons_thermodynamic_properties(*properties_data)
ax.set_ylabel("Thermodynamic Properties")
ax.set_xlabel("Temperature (K)")
plt.savefig("thermodynamics.png")
'

  • Calculate phonon dispersion curves of diamond using Density Functional Perturbation Theory (DFPT) as implemented in Quantum ESPRESSO.

  • DFPT allows for the analytical computation of the dynamical matrix.

  • Visualize the results with the AMSbands GUI or the Python PLAMS library.

_images/DiamondPhonons.png

IR/Raman Spectra

Input File (run from command-line or the AMSinput GUI)
#!/bin/sh

export SCM_DISABLE_MPI=1
export AMS_JOBNAME=BeO

"$AMSBIN/ams" --delete-old-results << EOF

Task GeometryOptimization

Properties
  NormalModes Yes
  Raman Yes
End

System
  Atoms
             Be       0.0000000000       1.5555413800       0.0007009000
             Be       1.3471383600       0.7777706900       2.1887103500
              O       0.0000000000       1.5555413800       1.6512462200
              O       1.3471383600       0.7777706900       3.8392556700
  End
  Lattice
         2.6942767100     0.0000000000     0.0000000000
        -1.3471383600     2.3333120800     0.0000000000
         0.0000000000     0.0000000000     4.3760188900
  End
End

Engine QuantumEspresso
  System
    ecutwfc 25.0
  End
  K_Points automatic
     4 4 4 0 0 0
  End
  Pseudopotentials
    Files Label=Be Path=QE/Be.pz-mt_fhi.UPF
    Files Label=O Path=QE/O.pz-mt_fhi.UPF
  End
EndEngine

EOF

  • Calculate the infrared and Raman spectra of BeO using DFPT

  • Use norm-conserving pseudopotentials

  • Raman only available for LDA

  • Visualize the calculated IR and Raman spectra, and also the corresponding vibrational modes with the program $AMSBIN/amsspectra

_images/IRRamanSpectra.png

PESScan: volume scan

Input File (run from command-line or the AMSinput GUI)
#!/bin/sh

export SCM_DISABLE_MPI=1

"$AMSBIN/ams" --delete-old-results <<EOF

Task PESScan
System
    Atoms
        Mg 0.000 0.000 0.000
         O 2.105 2.105 2.105
    End
    Lattice
        0.000 2.105 2.105
        2.105 0.000 2.105
        2.105 2.105 0.000
    End
End
PESScan
    CalcPropertiesAtPESPoints Yes
    ScanCoordinate
        nPoints 5
        CellVolumeScalingRange 0.9 1.2
    End
End

Engine QuantumEspresso
    K_Points automatic
        2 2 2 0 0 0
    End
    Properties
       DOS Yes
       BandStructure Yes
    End
    DOS
        K_Points automatic
            10 10 10 0 0 0
        End
    End
    BandStructure
        K_Points ams_kpath
        End
    End
EndEngine

EOF

  • Use the PESScan task in combination with the Quantum ESPRESSO engine. It performs a series of geometry optimization calculations while systematically varying the cell volume of MgO.

  • The density of states (DOS) and band structure are calculated for each volume.

  • You can analyze the results with the program $AMSBIN/amsmovie.

_images/PESScan.png

Replay

Command-line runscript
#!/bin/sh

export SCM_DISABLE_MPI=1

AMS_JOBNAME=PESScan "$AMSBIN/ams" --delete-old-results <<EOF

Task PESScan

System
    Atoms
        Mg 0.000 0.000 0.000
         O 2.105 2.105 2.105
    End
    Lattice
        0.000 2.105 2.105
        2.105 0.000 2.105
        2.105 2.105 0.000
    End
End

PESScan
    ScanCoordinate
        nPoints 3
        CellVolumeScalingRange 0.9 1.2
    End
End

Engine QuantumEspresso
    K_Points automatic
        2 2 2 0 0 0
    End
EndEngine

EOF

AMS_JOBNAME=Replay "$AMSBIN/ams" --delete-old-results << EOF

Task Replay

Replay
    File PESScan.results/ams.rkf
End

Properties
    Gradients Yes
    StressTensor Yes
End

Engine QuantumEspresso
    K_Points automatic
        5 5 5 0 0 0
    End
EndEngine

EOF

This example demonstrates a two-step approach for efficient property calculations. Initially, a PESScan task is performed with a low-precision setup (e.g., coarse k-point grid) to quickly generate a series of structures, using a cell volume scaling for MgO as a prototype system. Then, the Replay task is used to evaluate properties like gradients and stress tensors at a higher precision (e.g., finer k-point grid) for the selected structures.

_images/Replay.png

Born-Oppenheimer Molecular Dynamics

Input File (run from command-line or the AMSinput GUI)
#!/bin/sh

export SCM_DISABLE_MPI=1

AMS_JOBNAME=MolecularDynamics "$AMSBIN/ams" --delete-old-results << EOF

Task MolecularDynamics
RNGSeed 10

MolecularDynamics
    NSteps 10
    Trajectory
        SamplingFreq 1
        EngineResultsFreq 0
    End
    Checkpoint
        Frequency 1
    End
    InitialVelocities
        Temperature 300
    End
End

System
    Atoms
        O  0.77656125  0.70226469 -0.77898886
        H  0.18695701  1.27832345 -0.18188342
        H  1.36427986  1.27137397 -1.38443744
        O -0.77660318 -0.83048394  0.77894720
        H -0.18661066 -0.26385475  1.38473471
        H -1.36396069 -0.25091023  0.18224739
    End
    Lattice
         3.10979012 0.00175445 -0.000372438
        -0.00721068 3.06655157 -0.007924867
        -3.8697e-05 0.00424969  3.111852930
    End
End

Engine QuantumEspresso
EndEngine

EOF

  • Born-Oppenheimer Molecular Dynamics (BOMD) simulation with the AMS Driver

  • Analyze the resulting trajectory with the program $AMSBIN/amsmovie

_images/MolecularDynamics.png

PES Exploration

Input File (run from command-line or the AMSinput GUI)
#!/bin/sh

export SCM_DISABLE_MPI=1

"$AMSBIN/ams" --delete-old-results << EOF

Task PESExploration
PESExploration
    Job SaddleSearch
    RandomSeed 10
    Optimizer
        ConvergedForce 0.05
    End
    SaddleSearch
        DisplaceMagnitude 0.01
        RelaxFromSaddlePoint Yes
    End
End
System
    Atoms
        O       3.63620880       3.57049155       4.48487828
        C       4.48799778       4.50659100       4.51176734
        O       5.64352871       4.78595471       4.54849633
        H       3.09645968       4.80015429       4.45130367
        H       3.65975624       5.66218780       4.46883580
    End
    Lattice
        9.0 0.0 0.0
        0.0 9.0 0.0
        0.0 0.0 9.0
    End
End

Engine QuantumEspresso
    System
        ecutwfc 30.0
        ecutrho 120.0
        assume_isolated Martyna-Tuckerman
    End
    K_Points automatic
        1 1 1 0 0 0
    End
    NormalModes
        asr crystal
    End
EndEngine

EOF

This example demonstrates the use of the Quantum ESPRESSO engine in combination with the PESExploration task. The initial structure is a guess to the transition state of the reaction \(H_2+CO_2 \longrightarrow HOCHO\). Here, AMS locates the actual transition state and the corresponding reactants and products in an automated fashion.

_images/PESExploration.png