The three-dimensional spectrum generated by scanning the @[email protected] at incremental steps of @[email protected] @[email protected] (\(x\) axis = emission @[email protected], \(y\) axis = excitation @[email protected], \(z\) axis = emission flux) is called a (@[email protected], @[email protected]) [email protected]@ (or EES). The spectra are particularly useful for investigating samples containing more than one emitting species. Corrected EES are obtained if (a) the emission is corrected for instrumental response with @[email protected], and (b) the exciting radiation flux in photons \(\text{s}^{-1}\) is held constant for all excitation wavelengths.