Li3

Li3 is a term used in various scientific contexts to denote different lithium-containing systems. Its meaning depends on the field: it can refer to a hypothetical nucleus, a small lithium cluster, or a specific molecular species composed of three lithium atoms.

In chemistry and molecular physics, Li3 commonly denotes the triatomic lithium molecule, a bound state of three lithium atoms. Li3 is studied as part of lithium clusters Li_n and has been observed or inferred in ultracold atomic gases and in molecular-beam experiments under carefully controlled conditions. The ground-state geometry is predicted to be triangular, and its vibrational spectrum is relatively sparse because of weak binding, making direct detection challenging. The study of Li3 informs understanding of bonding in metal clusters and the transition from atomic to molecular behavior in lithium systems.

In nuclear physics, Li-3 (lithium-3) would be an isotope with three protons and zero neutrons. Such a nucleus is not bound and has not been observed as a stable state; if formed, it would be extremely short-lived and decay rapidly, illustrating the limits of nuclear binding near the proton drip line for light elements.

Li3 also appears in computational or theoretical contexts as shorthand for lithium trimers or small lithium clusters used in simulations of nanoscale materials and cold-atom physics.