The exponent parameter, 𝞯, controls the width of STOs. The exponential term dependent on the distance between nucleus and electron (r) shows the exact behaviour of the orbitals for the hydrogen atom. Furthermore, the exponential dependent term ensures the fairly rapid convergence with an increasing number of functions. Since STOs do not have any radial nodes, therefore linear combinations of STOs have been introduced, which shows the nodes in radial parts. The STOs are generally used in atomic and diatomic systems which require high accuracy.