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Redox Potential

Predict relative redox potentials for a molecule by computing electronic energy differences between neutral, reduced (one extra electron), and oxidized (one fewer electron) states.

The workflow produces relative redox potentials — energy differences in eV — not absolute potentials referenced to any electrode. Each redox state is geometry-optimised before a single-point energy evaluation.

from atomiverse import Atoms, RedoxPotential
from atomiverse.levels import GFN2_XTB

water = Atoms.from_smiles("O")

job = RedoxPotential(
    atoms=water,
    charge=0,
    multiplicity=1,
    optimization_level_of_theory=GFN2_XTB,
    single_point_energy_level_of_theory=GFN2_XTB,
)
job.submit()

result = job.require_result()
print(f"Reduction potential (rel.): {result.reduction_potential:.3f} eV")
print(f"Oxidation potential (rel.): {result.oxidation_potential:.3f} eV")

Inputs​

atoms is the starting neutral molecule geometry.

charge and multiplicity describe the total charge and spin multiplicity of the neutral molecule.

optimization_level_of_theory selects the method used for geometry optimisation of all three redox states (neutral, reduced, oxidized).

single_point_energy_level_of_theory selects the method for single-point energy evaluation on the optimised geometries. This is typically a higher-level method than the optimisation method.

Results​

result.reduction_potential is the relative reduction potential in eV, computed as the single-point energy difference between the neutral and reduced states.

result.oxidation_potential is the relative oxidation potential in eV, computed as the single-point energy difference between the oxidized and neutral states.

result.neutral_single_point_energy is the single-point energy of the optimised neutral molecule in Hartree.

result.neutral_optimization_energy is the energy after geometry optimisation of the neutral molecule in Hartree.

result.reduced_single_point_energy, result.reduced_optimization_energy, result.oxidized_single_point_energy, and result.oxidized_optimization_energy provide the individual energies for the charged states.

Important Notes​

  • The reported potentials are relative energy differences only. They are not calibrated against any reference electrode and should be used for comparing trends within a series, not as absolute predictions.
  • The reduced state is constructed by adding one electron (charge − 1, multiplicity forced to 2).
  • The oxidized state is constructed by removing one electron (charge + 1, multiplicity forced to 2).
  • Both reduction and oxidation are always computed — there is no option to run only one direction.

Compute Resources​

CPU cores and memory are determined automatically based on the molecule size and level of theory. The walltime estimate accounts for up to three geometry optimisations (neutral, reduced, oxidized) plus three single-point evaluations.