The ‘l’ or the Azimuthal quantum number itself is the magnitude of Orbital angular momentum or subsidiary quantum number. It defines the three-dimensional structure of an orbital.

For a given value of n, l can have n values ranging from 0 to n – 1.

o Other 3 quantum numbers: n, m and s are not related to orbital angular momentum.

• The principal quantum number n signifies the shell in which the electron is found, size and energy of an orbital to a large extent. It is a positive integer N=1,2,3,4.........

• The magnetic orbital quantum number or m provides the idea of the spatial distribution of an orbital with respect to co-ordinate axes. For any value of sub-shell ‘l’, m will have 2l+1 values.

• The electron spin quantum number or s is related to the spin of an electron as an electron spins around its axis
(like the earth) and s gives information of orientation of this spin of electrons.