Neutron skin is an exotic phenomenon that occurs in unstable nuclei. In this study, the various effects of the neutron skin on nuclear reactions and their relationship with the properties of nuclear structures are reviewed. Based on numerous studies using theoretical models, strong correlations have been found between the neutron skin thickness and the neutron removal cross section, neutron/proton yield ratio, $$\hbox {t}/{^3\hbox {He}}$$t / 3 He yield ratio, neutron–proton momentum difference, isoscaling parameter, photon production, reaction cross sections for neutron-induced reactions, charge-changing cross-sectional differences of mirror nuclei, astrophysical S-factor, and other quantities in nuclear reactions induced by neutron-rich nuclei. Moreover, the relationships between the neutron skin thickness and certain properties of the nuclear structure, such as $$\alpha$$α -cluster formation, $$\alpha$$α decay, nuclear surface, nuclear temperature, and proton radii difference of mirror nuclei, have also been investigated. Furthermore, it has also been shown that the neutron skin plays a crucial role in relativistic heavy-ion collisions. Experimentally, an unstable nucleus with a neutron skin can be generated by radioactive nuclear beam facilities, and the thickness of the neutron skin can be extracted by measuring the sensitive probes, which further helps impose stringent constraints on the equation of state of asymmetric nuclear matter and the properties of neutron stars.

The influences of $\alpha$-clustering configurations on the giant dipole resonance (GDR) in hot compound systems are discussed under the framework of an extended quantum molecular dynamics (EQMD) model. The computed GDR spectra in the hot nucleus ${}^{28}\mathrm{Si}$ are split into two peaks which are very consistent with the experimental measurement and are remarkably sensitive to the configurations of projectile ${}^{16}\mathrm{O}$, including the linear chain, kite, square, and tetrahedron configurations. Meanwhile, the sensitivity of the GDR lineshapes to the configurations of ${}^{16}\mathrm{O}$ gradually increases with angular momentum. However, for the fusion system induced by ${}^{20}\mathrm{Ne}$, their GDR lineshapes in ${}^{47}\mathrm{V}$ and ${}^{32}\mathrm{S}$ are mostly independent of the $\alpha$-clustering configurations compared with those in the hot compound systems induced by the projectile ${}^{16}\mathrm{O}$, which may be attributed to their much more similar geometric structures between the square pyramid and trigonal bipyramid configurations in ${}^{20}\mathrm{Ne}$. Additionally, we find that the GDR lineshapes in hot compound systems are sensitive to the geometric distributions of the projectile in phase space when it is compared to those with Woods-Saxon distribution and polarization in projectiles. These results demonstrate that the GDR can be taken as an experimental observable to extract information about the configurations of reaction systems.