Nuclear shell closures are at \( N,Z=2,8,20,28,50,82,126 \), and subshell closures at \( N,Z=2,6,8,14,16,20,28,32,34,40,50,\ldots \).
In the physics of nuclei, the evolution of nuclear structure as neutrons are added (or removed) from an isotope is a key
interest. Examples are the rare isotopes of helium (He-8,10) oxygen (O-22,24,28), calcium (Ca-52,54,60), nickel (Ni-78) and tin (Sn-100,132). The coupled-cluster method has the potential to address questions regarding these nuclei, and in a several cases was used to make predictions before experimental data was available. In addition, the method can be used to compute neighbors of nuclei with closed subshells.