Particle in a box
Quantum Chemistry (UG) · Chemistry
Molecule viewer
Interactive 3DBall-and-stick models with true bond angles — switch molecule to compare shapes.
Controls
Drag the sliders or type a value — the simulation updates live.
Study notes
An electron is trapped in a 1 nm box. Find the n=1 → n=2 transition energy and the light wavelength absorbed. Step 1: Eₙ = n²h²/8mL². ΔE = E₂ - E₁ = 3h²/8mL². Step 2: h = 6.626×10⁻³⁴ J·s, m = 9.11×10⁻³¹ kg, L = 10⁻⁹ m. Step 3: ΔE = 3(6.626×10⁻³⁴)²/(8×9.11×10⁻³¹×10⁻¹⁸) ≈ 1.8×10⁻¹⁹ J. Step 4: λ = hc/ΔE ≈ 1100 nm (infrared). A smaller box would absorb visible light — the basis of dye colours!