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Atomic Orbitals

page2011-04-04

Real-time 3D plots of the hydrogen atom’s electron orbitals, ray-marched in a WebGL fragment shader. Pick an orbital by its quantum numbers, choose how to project the wavefunction onto the screen, and drag the cloud around to explore its structure — the notes below the controls explain what each number and mode means.

interactive · Atomic Orbitals — WebGLopen ↗

Interactive demo: Atomic Orbitals — WebGL. Requires JavaScript to run — the source is at /interactive/atomic-orbitals-demo-1.html.

The two historic renders: the translucent cloud that ray-sums the probability density along every line of sight, and the solid surface that thresholds it — the two faces of the same wavefunction.

Translucent ray-summed render of a hydrogen orbital, lobes glowing red and blue
Translucent cloud — brightness accumulates along the line of sight.
Solid isosurface render of a hydrogen orbital with red lobes and a blue toroidal ring
Solid surface — the isosurface of the wavefunction at a threshold.

Where the electron is

Squash the 3D cloud onto its radial coordinate and the shells appear. This widget plots the radial probability of hydrogen’s eigenstates against two classical answers — the dwell time of a Kepler orbit, and what relativity does to it.

interactive · radial probability for hydrogen: quantum shells, classical Kepler dwell time, relativistic correctionopen ↗

Interactive demo: radial probability for hydrogen: quantum shells, classical Kepler dwell time, relativistic correction. Requires JavaScript to run — the source is at /interactive/probability/coulomb.html.

The shapes are polynomials

The angular part of every orbital — the thing that makes an s a sphere, a p a dumbbell, a d a cloverleaf — is a homogeneous polynomial of degree ℓ that the Laplacian kills. This widget counts them: of the (ℓ+1)(ℓ+2)/2 monomials of degree ℓ, exactly 2ℓ+1 survive as the shapes of the subshell.

interactive · the harmonic polynomials of degree ℓ, and the 2ℓ+1 that surviveopen ↗

Interactive demo: the harmonic polynomials of degree ℓ, and the 2ℓ+1 that survive. Requires JavaScript to run — the source is at /interactive/funcspace/solid-harmonics.html.