by admin | Jun 5, 2015 | sem1
Chemiluminescence Chemiluminescence is the emission of light (luminescence), as the result of a chemical reaction. There may also be limited emission of heat. Given reactants A and B, with an excited intermediate◊, [A] + [B] → [◊] → [Products] + light For example, if...
by admin | Jun 5, 2015 | sem1
Phosphorescence Phosphorescence is a process in which energy absorbed by a substance is released relatively slowly in the form of light. This is in some cases the mechanism used for “glow-in-the-dark” materials which are “charged” by exposure...
by admin | Jun 5, 2015 | sem1
Fluorescence Fluorescence is the emission of light by a substance that has absorbed light or other electromagnetic radiation. It is a form of luminescence. In most cases, the emitted light has a longer wavelength, and therefore lower energy, than the absorbed...
by admin | Jun 5, 2015 | sem1
Intersystem crossing When an electron in a molecule with a singlet ground state is excited (via absorption of radiation) to a higher energy level, either an excited singlet state or an excited triplet state will form. A singlet state is a molecular electronic state...
by admin | Jun 5, 2015 | sem1
Internal Conversion Internal conversion is a transition from a higher to a lower electronic state in a molecule or atom. It is sometimes called “radiation less de-excitation”, because no photons are emitted. It differs from intersystem crossing in that,...
by admin | Jun 5, 2015 | sem1
Quantum Efficiency The “quantum efficiency” (Q.E.) is the ratio of the number of carriers collected by the solar cell to the number of photons of a given energy incident on the solar cell. The quantum efficiency may be given either as a function of...
