Definition of azobenzene

PFG Precision Optics - Precision Optics 12/24 LB

Photonics Dictionary

azobenzene: Azobenzene is a chemical compound consisting of two phenyl rings linked by a N=N double bond. It is well-known for its ability to undergo reversible photoisomerization, meaning it can switch between two isomeric forms (trans and cis) upon exposure to light of specific wavelengths.

Photoisomerization: Azobenzene can exist in two geometric isomers: trans (E) and cis (Z). The trans isomer is typically more stable and linear, while the cis isomer is bent due to the double bond rotation around the N=N bond.

Light sensitivity: The isomerization between trans and cis forms is induced by ultraviolet (UV) or visible light, depending on the substituents attached to the phenyl rings. This property makes azobenzene useful in molecular switches and actuators.

Azobenzene derivatives and polymers incorporating azobenzene units have been studied and used in various applications, including:

Molecular switches: For controlling molecular properties such as conductivity or fluorescence.

Optical data storage: As a component in rewritable optical data storage devices.

Photoresponsive materials: In responsive coatings, films, and surfaces that change properties upon exposure to light.

Biomedical applications: In drug delivery systems and biomaterials due to their ability to undergo reversible structural changes in response to light.

Azobenzene is a versatile compound known for its photoresponsive properties, particularly its ability to undergo reversible photoisomerization between trans and cis forms upon light irradiation. This property has led to its widespread exploration and application in fields ranging from materials science to biotechnology.