magic number
Quick Summary
In physics, "magic numbers" refer to specific quantities that indicate a stable structure in atomic and nuclear models.1
For atoms, these numbers correspond to the number of electrons in filled electron shells, such as 2, 10, 18, 36, 54, and 86. Elements with these electron counts, like noble gases, are chemically stable.1
In atomic nuclei, the magic numbers are 2, 8, 20, 28, 50, 82, and 126. Nuclei with these numbers of protons or neutrons exhibit increased stability, similar to the exceptionally stable alpha particle (helium nucleus). This stability arises from large energy gaps between filled and empty energy levels, creating shell structures.1
Clusters of atoms can also exhibit exceptional stability at certain sizes, analogous to magic numbers in nuclei and atoms. This stability is linked to the closing of electron shells within the cluster. For metal clusters, stable electron counts include 8, 20, 40, and 58.23
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clusterComparison with bulk matter…values of N, known as magic numbers, can take on unusually stable geometric structures that yield large binding energies, while others with different small values of N have no especially stable forms and therefore only relatively low binding energies. The binding energies of medium-size clusters vary rather smoothly with N,…
Read More…values of N, known as magic numbers, can take on unusually stable geometric structures that yield large binding energies, while others with different small values of N have no especially stable forms and therefore only relatively low binding energies. The binding energies of medium-size clusters vary rather smoothly with N,…
Read More- clusterStructure
…xenon and of the so-called magic number nuclei—i.e., the sequence of unusually stable atomic nuclei beginning with the α-particle, or helium nucleus. Such unusual stability suggests that its interpretation should be associated with the closing of some kind of shell, or energy level. The overall structure that determines the cluster’s…
Read More…xenon and of the so-called magic number nuclei—i.e., the sequence of unusually stable atomic nuclei beginning with the α-particle, or helium nucleus. Such unusual stability suggests that its interpretation should be associated with the closing of some kind of shell, or energy level. The overall structure that determines the cluster’s…
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