Description
Calculate one supplied Tafel-coordinate pair with an explicit current-density reference.
Electrochemical quantities require explicit electrode references, current sign, area definition and time basis. Geometric area differs from active-area conventions, charge differs from charge equivalents, and a logarithmic current coordinate needs a same-unit reference magnitude. Local sign changes and coordinate terms do not fit kinetics or establish a valid experiment.
Calculate one supplied Tafel-coordinate pair with an explicit current-density reference.
When to use this tool
Use Tafel Point Overpotential Coordinate when you already have currentDensity, currentDensityReferenceUnit, electrodePotential, referenceEquilibriumPotential and need to calculate one supplied Tafel-coordinate pair with an explicit current-density reference.
How to use the tool and how it works
- Enter currentDensity, currentDensityReferenceUnit, electrodePotential, referenceEquilibriumPotential. Use the units and conventions below.
- Run the tool. Correct any format, range, or cross-field input error before interpreting the output.
- Read log10AbsoluteCurrentDensity, overpotential. Use the output convention below.
Require currentDensity!=0 and currentDensityReferenceUnit positive/finite; log coordinate=log10(abs(currentDensity))-log10(referenceUnit), overpotential=electrodePotential-referenceEquilibriumPotential.1
Overpotential uses an electrode potential relative to equilibrium. Supplying both potentials on the same reference is essential; this helper does not establish that equilibrium value or a kinetic model.2
| Input field | Meaning and units | Accepted input |
|---|---|---|
| currentDensity | Current Density | Required. Finite number. |
| currentDensityReferenceUnit | Positive magnitude representing one reference current-density unit, expressed on the same numerical/unit basis as currentDensity. | Required. Finite number; strictly above 0. |
| electrodePotential | Electrode Potential | Required. Finite number. |
| referenceEquilibriumPotential | Reference Equilibrium Potential | Required. Finite number. |
| Output field | Interpretation | Returned shape |
|---|---|---|
| log10AbsoluteCurrentDensity | log10(abs(currentDensity)/referenceUnit), evaluated as a difference of logarithms. | Required. Finite number. |
| overpotential | Electrode potential minus supplied equilibrium potential; both require the same electrode reference and unit. | Required. Finite number. |
{
"input": {
"currentDensity": 100,
"currentDensityReferenceUnit": 1,
"electrodePotential": 0.5,
"referenceEquilibriumPotential": 0.3
},
"output": {
"log10AbsoluteCurrentDensity": 2,
"overpotential": 0.2
}
}Limitations and assumptions
- The reference is one positive current-density magnitude in the same units, making the logarithm dimensionless. No Tafel region, slope, exchange current, kinetics or junction correction is fitted.
- Inputs must satisfy both the field types and the cross-field conditions above. Invalid input causes an error; a successful false flag or documented placeholder is a different result.
- Numeric calculations use binary floating point unless exact decimal-integer arithmetic is explicitly stated. No hidden measurement tolerance or decimal rounding is added; nonfinite or out-of-contract results are rejected. Numeric signed-zero results are exported as zero.
Alternative or Complementary methods
Inspect calibrated instrument records, reference-electrode details, area definitions and the complete experiment before interpreting results. Use the full electrochemical model and verified operating conditions when a local current, charge, sweep or impedance-representation term cannot answer the scientific question.
References
Similar or alternative tools
- Electrode Potential Liquid Junction Offset
Subtract a supplied liquid-junction offset from a recorded potential.
- Current Density Area Reference
Calculate signed current per supplied reference area.