What is screening effect? How is it related

The screening effect, also known as the shielding effect, refers to the reduction in the effective nuclear charge experienced by an outer electron due to the presence of inner-shell electrons. The inner electrons act as a shield, reducing the electrostatic pull exerted by the positively charged nucleus on the outermost electrons.

Relation to Atomic Properties

• Ionization Energy: A stronger screening effect decreases ionization energy, as the outer electrons are less tightly bound to the nucleus.
• Atomic Size: Greater shielding leads to a larger atomic radius, as the outer electrons are held less tightly.
• Electron Affinity: The screening effect lowers electron affinity, as the nucleus's ability to attract additional electrons is reduced.

This effect is more pronounced in elements with higher atomic numbers due to the presence of more inner-shell electrons.