electron spin

physics

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Last updated

June 26, 2026

Quick Summary

Electron spin is an intrinsic form of angular momentum possessed by subatomic particles, including electrons. It's a quantum mechanical property that doesn't have a direct classical analogue, but it can be visualized as the particle spinning on its axis. This spin is quantized, meaning it can only take on specific discrete values, typically represented as +1/2 or -1/2 for electrons.12

This property is crucial for classifying particles into two main groups: fermions (like electrons, with half-integer spin) and bosons (with integer spin). The Pauli exclusion principle, which states that no two identical fermions can occupy the same quantum state simultaneously, relies on electron spin. This principle is fundamental to understanding atomic structure and how electrons arrange themselves in orbits. Electrons, due to their spin, also possess a magnetic moment, allowing them to interact with magnetic fields.12

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