Moseley's Law
Relates characteristic X-ray frequencies to atomic number. The screening constant b accounts for shielding by inner electrons (b ≈ 1 for Kα lines, b ≈ 7.4 for Lα lines).
Variables
Derivation
Moseley discovered this empirically, which helped establish atomic number as fundamental to element identity.
Your notes
Other modern physics formulas with the same quantities
- Electron Orbital Radius (Atomic Physics) shares Atomic number
Where this formula is listed
- Modern Physics formulas, under Atomic Physics, alongside Bohr Radius and Bohr Energy Levels.
- In the modern physics list it comes after Electron Orbital Radius and before Radioactive Decay Law.
- Modern Physics formula sheet, one of 41 formulas printed with symbol keys and SI units.
- The full formula index, grouped by category and topic.
Common questions
What is the Moseley's Law formula?
Moseley's Law is written √(f) = a(Z − b). Relates characteristic X-ray frequencies to atomic number. The screening constant b accounts for shielding by inner electrons (b ≈ 1 for Kα lines, b ≈ 7.4 for Lα lines). It belongs to Modern Physics, under Atomic Physics.
What are the units in √(f) = a(Z − b)?
In SI units, f is characteristic x-ray frequency, measured in Hz; a is proportionality constant, measured in Hz^(1/2); Z is atomic number (dimensionless); b is screening constant (dimensionless).
How is the Moseley's Law formula derived?
Moseley discovered this empirically, which helped establish atomic number as fundamental to element identity. The result is √(f) = a(Z − b).