In the article on Magnetism, it states that the physical cause of an atomic magnetic dipole (or moment) is two kinds of movement of electrons.
This article clarifies (‽) that electrons don’t actually move in their orbitals. When quantum mechanics refer to “electron orbital motion” they are actually referring to the spacial wave function of the electron.
Just as spin doesn’t mean the particle is actually spinning around an axis in the classical sense, orbital motion doesn’t mean the particle is revolving around the nucleus in the sense of the Bohr model. Likewise, the orbital angular momentum is a quantum value inherent in the electron’s orbital energy state, even though nothing is moving in the classical sense. Furthermore, current loops caused by this orbital motion are also linguistic licence on the part of physicists, because there is neither current (movement of a charge) nor looping going on; but, the mathematical description is very much like that of a classic current loop.
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