magnetic quantum number

In atomic physics, the magnetic quantum number is the third of a set of quantum numbers (the principal quantum number, the azimuthal quantum number, the magnetic quantum number, and the spin quantum number) which describe the unique quantum state of an electron and is designated by the letter m. The magnetic quantum number denotes the energy levels available within a subshell.
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(m ) Quantum number that labels different orbitals within a subshell . m can take on values from - to + . The number of orbitals in a subshell is the same as the number of possible m values.