Nanoclusters

Nanoclusters A nanocluster is a grouping of a number of nanoparticles. Nanoclusters have at least one dimension between 1 and 10 nanometers and a narrow size distribution. The size of nanoclusters ranges from sub-nanometer to 10 nm in the diameter. In nanotechnology,...

Photosensitization

Photosensitization Photosensitization is a reaction to light that is mediated by a light-absorbing molecule, which is not the ultimate target. Photosensitization can involve reactions within living cells or tissues, or they can occur in pure chemical systems. In...

Chemiluminescence

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...

Phosphorescence

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...

Fluorescence

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...

Intersystem crossing

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...