Practice question

Terminology for spectral changes distinguishes positional versus intensity effects. Bathochromic shift specifically describes displacement of absorption maximum toward longer wavelength and lower energy, analogous to red end of visible spectrum. It arises from extension of π conjugation, introduction of auxochromes, deprotonation, or increased solvent polarity that stabilizes π* excited state preferentially. Opposite movement toward shorter wavelength is hypsochromic or blue shift. Hyperchromic and hypochromic refer to increased or decreased intensity without λmax shift. Understanding bathochromic designation aids interpretation of protein unfolding, nucleic acid interactions and auxochrome effects in enzymology examinations.