Symmetries are known to play an important role in the low-lying level structure of Sn isotopes, mostly in terms of the seniority and generalized seniority schemes. In this paper, we revisit the multi-j generalized seniority approach for the first excited 2⁺ and 3⁻ states in the Cd (Z = 48), Sn (Z = 50) and Te (Z = 52) isotopes, where the Cd and Te isotopes represent two-proton hole and two-proton particle nuclei, thus involving both kind of particles (protons and neutrons) in contrast to Sn isotopes. Interestingly, the approach based on neutron valence space alone is able to explain the B(E2) and B(E3) trends respectively for the 2⁺ and 3⁻ states in all the three Cd, Sn and Te isotopes. The new results on the inverted parabolic behaviour of B(E3) values in Cd and Te isotopes are understood in a manner identical to that of Sn isotopes by using the generalized seniority scheme. No shell quenching is supported by these calculations; hence, the neutron magic numbers, N = 50 and N = 82, remain robust in these isotopic chains. It is quite surprising that the generalized seniority continues to be reasonably successful away from the semi-magic region, thus providing a unifying view of the 2⁺ and 3⁻ states.

众所周知，对称性在锡同位素的低位结构中起着重要作用，主要是在资历和广义资历方案方面。在本文中，我们重温多Ĵ对于第一激发2个广义资历方法⁺和3 ^-状态在CD（Ž = 48），锡（Ž = 50）和Te（Ž = 52）的同位素，将镉，其中Te同位素表示两个质子的空穴和两个质子的粒子核，因此与Sn同位素相反，涉及两种粒子（质子和中子）。有趣的是，仅基于中子价空间的方法就能够分别解释2 ⁺和3-的B（E2）和B（E3）趋势^。Cd，Sn和Te三种同位素的所有态 通过使用广义年资计划，可以以与Sn同位素相同的方式理解有关Cd和Te同位素中B（E3）值的倒抛物线行为的新结果。这些计算不支持外壳淬火。因此，在这些同位素链中，中子魔术数N = 50和N = 82仍然很健壮。它令人惊讶的是广义的资历仍然是从半魔区域相当成功了，从而提供了2个的一个统一的视图⁺和3 ^-状态。