Lamp-Sollux

A set of chromophores is usually excited by light and only in some cases by heat or an electric field (photoelectric effect). The ability to be excited by heat is due to the presence of electronic-vibrational transitions in the structure of the chromophore. The possibility of excitation by a strong electric field occurs in crystalline sensitizers.

In a light field, not all chromophores glow (luminesce), since luminescence is very often a thermal process and, as a consequence, the molecule is able to glow even after internal excitation is completed. A molecule that cannot glow would not glow when exposed to light, heat or electricity, so glow in the absence of photoexcitation is a direct indicator of excitation and an excited state.

The photonic processes that accompany the glow of most chromophores are described in the theory of radiation chemistry by three parameters of light radiation that characterize the spectral distribution of the light flux: monochromatic absolute photopotential, the width of the radiation peak and its shape in the spectrum.