A spectrum having distinct lines was observed for hydrogen. Rydberg gave a general relation between wave number and series of integers
Where 109677 cm-1 is called the Rydberg constant.
Depending upon the different valves of n1 and n2 , these spectral lines are devided into following groups (also called series). For each group of lines n1 is constant and n2 varies and have values (n1 + 1) and higher.
These spectral lines split up further in very closely spaced lines when the sample is placed in a magnetic field. This phenomenon is known as Zeeman effect.
