ThermodynamicsAdvanced Level

Defect Concentration Tool

Estimate equilibrium concentration of point defects (vacancies) in a crystal lattice at different temperatures.

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Vacancy Concentration

Equilibrium point defects in crystal lattice

Enter valid inputs to calculate defects.

Formula: Point Defect Thermodynamics

Nv / N = exp(-Qv / (kB · T))
Where:
Nv=Number of equilibrium vacancies (atoms/m³)
N=Total atomic lattice sites (atoms/m³)
Qv=Vacancy formation activation energy (eV/atom or J/mol)
kB=Boltzmann constant (8.617e-5 eV/K)
T=Absolute temperature (K)

Scientific Assumptions & Methodology

  • Applies to equilibrium vacancy state where Gibbs free energy is minimized.
  • Ignores vacancy-vacancy interactions, which is valid for dilute defect concentrations.
  • Assumes vibrational entropy contributions are negligible (or bundled into Qv).

Limitations & Educational Warnings

  • Represents equilibrium states only. Rapid quenching (fast cooling) will 'freeze in' non-equilibrium vacancy populations.
  • Approximate atomic density presets assume isotropic elemental solids.