The azimuthal quantum number (l) is a quantum number used in atomic physics to describe the shape of an electron’s orbital in an atom. It represents the angular momentum of the electron about the nucleus, and it can take on integer values from 0 to n-1, where n is the principal quantum number (n = 1, 2, 3, …).
The azimuthal quantum number determines the number of nodal planes (planes of zero electron density) in an orbital. For example, an s orbital (l = 0) has no nodal planes and is spherically symmetrical, while a p orbital (l = 1) has one nodal plane and is shaped like a dumbbell. Higher values of l correspond to more complex shapes and more nodal planes.
The azimuthal quantum number also determines the orbital’s magnetic quantum number (m), which specifies the orientation of the orbital in space. The magnetic quantum number can take on values ranging from -l to +l.
Together with the principal quantum number and the magnetic quantum number, the azimuthal quantum number helps to define the electron configuration of an atom and is used to predict the energies, Admission Management and spectra of atomic transitions.