Yelement

Yelement is a fictional chemical element used in speculative science, worldbuilding, and some fictional universes. In most portrayals, it is a superheavy metal with atomic number 164 and the symbol Ye. It is not recognized by real-world chemistry or IUPAC, and no empirical evidence of its existence has been reported.

Origin and discovery: In fictional contexts, Yelement is typically described as having been first synthesized in particle-accelerator experiments in the mid-22nd century by a multinational collider consortium. It is produced by fusing lighter transactinide nuclei under extreme energy and neutron-rich conditions. Because of rapid radioactive decay, researchers generally observe only short-lived isotopes.

Properties: Predicted properties include high atomic mass, high density, and strong relativistic effects that influence its chemistry. Yelement is described as forming multiple oxidation states, commonly +2, +3, and +4, with oxides and halides predicted to be highly reactive. Compounds of Ye are often depicted as color-rich, with unusual bonding due to relativistic contraction of s- and p-orbitals. The element is commonly met in a postulated group adjacent to the transactinides in fictional periodic tables.

Isotopes and decay: Theoretical isotopes of Yelement would range widely in stability; in many stories the most persistent isotope is Ye-272 or Ye-273 with half-lives from milliseconds to seconds, while some narratives explore longer-lived alternatives. In reality, no stable or observed isotopes exist.

Applications and depiction: In fiction, Ye is proposed as a source of unique energy via hypothetical nuclear reactions, or as a basis for advanced materials with extreme strength or superconductivity. Ethical and safety issues are often explored, given its radioactive hazards and production challenges in fictional settings.

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