Atomic Orbitals A Quantum Mechanical Description of Electrons Around the Nucleus

ATOMIC ORBITALS A QUANTUM MECHANICAL DESCRIPTION OF ELECTRONS AROUND THE NUCLEUS 

The classical description of the atom (Bohr theory) assumed that electrons move on trajectories around the nucleus. The energy of each electron was thought to relate to the electron s distance from the nucleus. This view is intuitively appealing because it coincides with our physical understanding of classical mechanics. Yet it is incorrect for several reasons. 

an electron moving in an orbit would give rise to the emission of electromagnetic radiation, which is characteristic of any moving charge. The resulting energy loss from the system would cause the electron to spiral toward the nucleus, a prediction that is completely at odds with reality. 

Second, Bohr theory violates the Heisenberg uncertainty principle, because it defines the precise position and momentum of an electron at the same time. 

Classical atom electrons In orbit around the nucleus 

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