halene

Halene is a term that appears in historical or informal chemical usage to refer to halogenated hydrocarbons, but it does not have a single, formal definition in modern nomenclature. In older literature the word was used in different ways, leading to variability in meaning across sources. Because of this lack of standardization, halene is largely considered obsolete in contemporary chemistry.

Historically, halene has been described as encompassing hydrocarbons that contain halogen substituents. In some accounts it was applied more narrowly to halogenated alkenes—compounds that possess one or more carbon–carbon double bonds with attached halogens. In other sources, the term was used more broadly to denote any hydrocarbon derivative that includes halogen atoms. The absence of a precise, universally accepted definition means the term can be ambiguous unless the author provides a specific context.

In modern practice, established categories such as alkyl halides, vinyl halides, aryl halides, and haloalkenes are preferred for clarity. These terms align with systematic naming conventions and allow precise description of structure and reactivity. Because halene is not part of current IUPAC nomenclature, it is encountered mainly in historical discussions, antiquated texts, or when tracing the evolution of halogenated compound terminology.

Outside chemistry, the term may also appear as a surname or in fictional contexts, but such uses are distinct from its historical chemical sense. For practical purposes, readers should rely on standard classifications when identifying or discussing halogenated hydrocarbons. See also halogen, alkene, haloalkane.