Why we need to know about atomic physics ?



Atomic physics is study related with structure of the atom,
its energy states, and its interactions with other particles and with electric
as well as magnetic fields. Atomic physics is the road to Quantum physics, which
is one of the cornerstones of modern physics.

There are three different aspects to atomic physics:



1. The electronic structure of atoms- Bohr’s model, Schrödinger
model.



2. Spectroscopic techniques to measure electronic transition
between different states.



3. The variety of chemical elements represented by the
periodic table and their properties.

In 1926, Austrian physicist Erwin Schrödinger proposed an
equation which completely changes the scientific world of atomic physics.
Before Schrödinger there were some other atomic models like Bohr model but they
were not able to explain the relative intensities of spectral lines and the
Zeeman Effect, when the spectral line is split into several components in the
presence of a magnetic field. But Schrödinger’s Equation changes the scenario
as it describes the wave function or state function of a quantum-mechanical
system i.e. atomic system.

Now let’s take a look on its significance- the equation
which won the Nobel Prize in 1931, Schrodinger wave function has multiple
unique solutions representing characteristic radius, energy, amplitude.
Probability density of the electron calculated from the wave function shows
multiple orbitals with unique energy and distribution in space.

The time independent Schrödinger equation:-



Atomic physics can be globally separated into two different
branches:-



1.     One is dedicated to the study of bound state
systems. Many different tools have been developed to deal with one electron and
many electron atoms.

1.     The
second branch is associated with all those processes related to collision
problems.

Significance of Atomic Physics’:-

Atomic Physics is the branch of science that deals with the
structure of the electron cloud within atoms. It regards the nucleus of the
atom as a point charge of certain mass, without making any assumptions about
its structure, which is the subject of Nuclear Physics. At the other limit of
its characteristic length scale, atomic physics is neighbour to Molecular
Physics and, in a wider sense, Chemistry, i.e. the interaction of atoms with
each other and the structure of the resulting molecular electron systems.

All of these subjects draw heavily on Quantum Mechanics for their theoretical foundation because the states electrons can occupy in an atom or molecule are different solutions of the Schrödinger equation