Radicalmolecule

Radicalmolecule is a term occasionally used to describe a molecule that exhibits radical character, typically meaning it contains at least one unpaired electron in its electronic structure. In standard chemical usage, such species are called radicals; the one-word form radicalmolecule is not widely adopted in formal nomenclature. When present, the unpaired electron gives the molecule a spin multiplicity of doublet (or higher if there are multiple unpaired electrons) and usually imparts high reactivity and paramagnetism.

Radical molecules can be stabilised by delocalization of the unpaired electron over conjugated systems or by steric protection from bulky substituents. They may form transiently in chemical reactions, through homolytic cleavage of a bond, photolysis, or redox processes, and some are deliberately generated as reactive intermediates in synthesis or polymerization.

Detection and characterization commonly rely on electron paramagnetic resonance (EPR) spectroscopy, which directly observes unpaired electrons, supported by UV-Visible spectroscopy and mass spectrometry to infer structure. Computational methods, such as density functional theory (DFT), are often used to predict spin density and stability.

In practical terms, radicalmolecules are important in atmospheric chemistry (for example hydroxyl and peroxy radicals), combustion, polymerization processes, and organic synthesis via radical pathways. Their high reactivity requires controlled handling to prevent unwanted side reactions. The term remains more of a descriptive descriptor than a formal systematic category in most chemical literature.