Davisson-Germer Experiment (Bragg's Law for Electrons) (2d sinφ = nλ (Bragg diffraction confirms de Broglie)
jee-mainjee-advancedneet-ug
2d sinφ = nλ (Bragg diffraction confirms de Broglie wavelength)
What each symbol means
| Symbol | What it stands for |
|---|---|
| d | Crystal lattice spacing (m) |
| h | Planck constant (6.626×10⁻³⁴ J·s) |
| n | Order of diffraction (integer) |
| p | Electron momentum (kg·m/s) |
| λ | de Broglie wavelength of electrons (m) |
| φ | Glancing angle of incidence/scattering |
When to use this
Electrons scattered off Ni crystal. Peak at 54 V accelerating voltage, φ=50°. Measured λ matches h/p = h/√(2meV). Confirmed wave nature of electrons.