Fe23

Fe23 is not a standard chemical symbol or a recognized isotope for iron. Iron has several stable isotopes, notably Fe-54, Fe-56, Fe-57, and Fe-58. An isotope with mass number 23 would require 23 nucleons but only 26 protons, which is not possible, so Fe-23 does not exist in nuclear chemistry or nucleide databases.

In materials science and cluster chemistry, Fe23 may appear as a shorthand for a cluster or nanoparticle composed of 23 iron atoms (often written as Fe23). Such clusters are studied as model systems for metallic bonding, magnetism, and size-dependent properties. They are not defined as a fixed stoichiometric compound but as finite assemblies that can adopt different geometric isomers, potentially resembling close-packed fragments of the face-centered cubic lattice or icosahedral-like structures. Studies typically use techniques such as mass spectrometry and spectroscopy, complemented by theoretical methods like density functional theory, to explore structure and magnetic behavior.

In other contexts, Fe23 may represent a typographical error or a fragment of a longer formula within a publication or database entry. It is not a standard designation for a known iron-containing material, such as cementite (Fe3C), iron oxides, or common iron alloys.

Conclusion: Fe23 is ambiguous and not recognized as a formal chemical entity. When encountered, it is important to check the source for context, as it could refer to an iron cluster, a misprint, or be shorthand within a larger notation.