What did bohr contribute to modern atomic theory

He created an atomic model and Bohr diagram, if that could be it.

Bohr atomic model

Explanation:

Bohr's atomic model:

Bohr's atomic model was proposed by Neil Bohr in 1913. In this atomic model Neil Bohr's modified the Rutherford Model and show how electrons in an atoms moves around the nucleus in stable orbits. According to Rutherford model electron's in atoms are filled in orbits and these electron moves around the nucleus in these orbits like planets moves around the sun in fixed orbit but Rutherford's model was unable to show the stability of orbits. To solve this problem, Bohr proposed a new model b. According to this model electrons move around the nucleus in fixed size orbits which have fixed energy and the electron with low energy is filled in smaller size orbit. Radiation are emitted from atoms only when transition of electron from higher energy orbit to lower energy orbit takes place.