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Laporte allowed and spin allowed transitions wavelength and intensities
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Laporte and spin selection rules govern the probabilities of electronic transitions in atoms and molecules.
Laporte Rule: States that transitions between orbitals of the same parity (both s, both p, etc.) are forbidden. This means a transition from an s orbital to another s orbital is forbidden, while a transition from an s orbital to a p orbital is allowed. This rule is based on the symmetry of the orbitals.
Spin Selection Rule: States that transitions involving a change in spin multiplicity are forbidden. This means a transition from a singlet state to a triplet state (or vice versa) is forbidden. The spin multiplicity is determined by the total spin angular momentum of the electrons.
These rules explain why certain transitions are more intense (allowed) than others. While these rules are generally followed, there can be exceptions. However, the intensity of transitions is still influenced by these selection rules.
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