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Laporte allowed and spin allowed transitions would give what color in uv Vis spectrum
Accepted Answer
Laporte and spin selection rules in UV-Vis spectroscopy dictate which electronic transitions are allowed and thus produce strong absorption bands.
Laporte rule: Transitions between orbitals of the same parity (both s, both p, etc.) are forbidden. Transitions between orbitals of different parity (s to p, p to d, etc.) are allowed.
Spin selection rule: Transitions where the spin multiplicity changes (e.g., singlet to triplet) are forbidden. Transitions where the spin multiplicity remains the same (e.g., singlet to singlet) are allowed.
Since the color observed in a UV-Vis spectrum is due to the absorption of specific wavelengths of light, allowed transitions (both Laporte and spin allowed) will result in stronger absorption bands and therefore more intense colors. Conversely, forbidden transitions will produce weaker bands and less intense colors.
It's impossible to definitively say what color a specific molecule will exhibit in a UV-Vis spectrum based solely on these rules, as other factors like the specific orbitals involved, the energy levels, and the solvent used also play a significant role. However, the combination of these rules provides a useful framework for understanding the intensity and color of the observed absorption bands.
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