Definition
Spectral shifts refer to changes in the position and intensity of absorption bands in a spectrum, influenced by molecular structure, substituents, and environmental factors.
Types of Spectral Shifts
Bathochromic Shift (Red Shift):
Shift to longer wavelengths (lower energy).
Caused by electron-donating groups or extended conjugation.
Hypsochromic Shift (Blue Shift):
Shift to shorter wavelengths (higher energy).
Resulting from electron-withdrawing groups or reduced conjugation.
Hyperchromic Effect:
Increase in absorption intensity.
Occurs due to increased probability of electronic transitions.
Hypochromic Effect:
Decrease in absorption intensity.
Caused by structural changes that reduce transition probabilities.