Coexistence phenomena of chemical-bonding-like structures in neutron excess systems

本文将能处理一般双中心体系中共价组态和原子组态的广义双中心集团模型（GTCM）应用于轻中子过剩体系12 Be = . + . + 4N。激发能级的本征结构进行了研究。我们发现，在未结合区，离子结构。8He和5 He +7 He的原子结构，6 He +6 He的原子结构，虽然在结合区的共价结构占主导地位。一个奇异的超形变，它具有共价和He-二聚体结构的混合配置，也实现了在同一能量区域。这些未束缚态的水平计划揭示了一个强大的简并功能与相当大的不同配置的混合物。本研究结果有力地表明，这种简并特征可以推广到轻质量区的一般中子过剩系统。

The generalized two-center cluster model (GTCM), which can treat covalent and atomic configurations in general two center systems, is applied to the light neutron-excess system, 12Be = . + . + 4N. The intrinsic structure of the excited energy levels is investigated. We found that, in an unbound region, the ionic structures of .+8He and 5He+7He, the atomic structure of 6He+6He are generated although the covalent structures are dominant in the bound region. An exotic superdeformation, which has a hybrid configuration of both the covalent and He-dimer structures, is also realized in the same energy region. The level scheme of these unbound states reveals a strong degenerate feature with a considerable mixture of the different configurations. The present result strongly suggests that such a degenerate feature can be generalized to general neutron-excess systems in the lighter mass region.