Superatom

Superhalogens are atom clusters with a higher electron affinity than chlorine, the atom with the highest electron affinity (3.62 eV). The concept was first formalized by and Alexander I. Boldyrev in 1981. They were first clearly experimentally identified in 1999, precipitating a wave of subsequent research in the field. ==Superalkalis==

Superalkalis are atom clusters with a lower ionization energy than caesium, the atom with the lowest ionization energy (3.89 eV). The concept was first formalized by Gutsev and Boldryev in 1982. ==Aluminium clusters==

Certain aluminium clusters have superatom properties. These aluminium clusters are generated as anions ( with n = 1, 2, 3, … ) in helium gas and reacted with a gas containing iodine. When analyzed by mass spectrometry one main reaction product turns out to be . These clusters of 13 aluminium atoms with an extra electron added do not appear to react with oxygen when it is introduced in the same gas stream, indicating a halide-like character and a magic number of 40 free electrons. Such a cluster is known as a superhalogen. The cluster component in ion is similar to an iodide ion or better still a bromide ion. The related cluster is expected to behave chemically like the triiodide ion. It is particularly easy and reliable to study atomic clusters of inert gas atoms by computer simulation because interaction between two atoms can be approximated very well by the Lennard-Jones potential. Other methods are readily available and it has been established that the magic numbers are 13, 19, 23, 26, 29, 32, 34, 43, 46, 49, 55, etc. • = the property is similar to germanium atoms. • = the property is similar to halogen atoms, more specifically, chlorine. • , where . • = the property is similar to alkaline earth metals. • , where . ==Other clusters==

• = the interior causes 2 valence electrons from the Li to orbit the entire molecule as if it were an atom's nucleus. • = has one diffuse electron orbiting around core, i.e., mimics an alkali-metal atom. • = has two diffuse electrons orbiting around core, i.e., mimics He-atom. • A cluster of 13 platinum atoms becomes highly paramagnetic, much more so than platinum itself. ==Superatom complexes==

Superatom complexes are a special group of superatoms that incorporate a metal core which is stabilized by organic ligands. In thiolate-protected gold cluster complexes, a simple electron counting rule can be used to determine the total number of electrons () which correspond to a magic number: :n_e = N\nu_A - M -z where is the number of metal atoms (A) in the core, is the atomic valence, is the number of electron withdrawing ligands, and is the overall charge on the complex. For example the Au102(p-MBA)44 has 58 electrons and corresponds to a closed shell magic number. Gold superatom complexes • • • Other superatom complexes • • • – In 2018 researchers produced 15-nm-thick flakes of this superatomic material. They anticipate that a monolayer will be a superatomic 2-D semiconductor and offer new 2-D materials with unusual, tunable properties. • Organo− Zintl-based superatoms: [] and [] • ==See also==