# Hypsochromic shift

$\Delta\lambda = \lambda^{\mathrm{state 1}}_{\mathrm{observed}} - \lambda^{\mathrm{state 2}}_{\mathrm{observed}}$ where $\lambda$ is the wavelength of the spectral peak of interest and $\lambda^{\mathrm{state 1}}_{\mathrm{observed}} > \lambda^{\mathrm{state 2}}_{\mathrm{observed}}$