Iodineon

Iodineon is a fictional chemical element that appears in speculative science fiction and worldbuilding. Named for its alleged similarity to iodine, it is described as a heavy halogen-like element with properties that vary across works.

In most depictions, iodineon behaves as a nonmetal with high electronegativity and a strong tendency to form diatomic molecules and interhalogen compounds. Its oxidation states are described variably, commonly including -1 and several positive states up to around +7. The solid is often portrayed as dense and brittle, with a proclivity to sublimate at modest temperatures.

There is no confirmed natural occurrence on Earth. In fiction, iodineon is produced in specialized laboratories, industrial reactors, or extracted from exotic extraterrestrial materials. Its synthesis is typically described as requiring high-energy processes or advanced catalysts, reflecting its status as a deliberately advanced or exotic element.

Proposed applications are speculative and diverse, ranging from catalysts and semiconductors to energy storage materials or components in propellant and nuclear-related technologies. Some stories treat iodineon compounds as highly reactive or luminescent, while others emphasize stability under extreme conditions.

Safety and regulation in imagined worlds often parallel those for real halogens and heavy nonmetals: handling is hazardous, toxicity is a concern, and containment is required to prevent environmental release. Because iodineon is fictional, definitions of its properties differ by source.