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849As was shown in [1,2], the phenomenon of cluster ing in self conjugate nuclei of the light and medium mass groups is important even for describing ground state nuclear properties. The limiting case of this phe nomenon could be occurrence of the Bose-Einstein condensate [3] or of states with extremely high defor mation close to chain configurations [4]. The most frequently arising case is, however, the occurrence of one valence alpha particle near the core, which leads to the octupole deformation of the entire nucleus and consequently to the occurrence of a family of rota tional bands.Rotational bands in light nuclei are often used to verify various cluster model predictions. Considerable progress in describing these bands in the 16 O and 20 Ne nuclei allowed us to investigate nuclei with a neutron excess. After the structure of the beryllium nuclei with different neutron numbers was successfully described within the AMD model [5], an attempt was made to predict the properties of rotational bands in the 22 Ne nucleus [6]. As is well known, the 20 Ne nucleus has many bands, most of which are well studied and exhibit a pronounced cluster nature, which allows a great variety of states to be expected in the case of neu tron excess.On the other hand, a great many experimental results have recently been obtained from investigating rotational bands in 18, 20 O [7, 8] and 22 Ne nuclei [9], which allows phenomenological analysis of the mani festation of clustering as a global property of light nuclei and the results to be compared with the predic tions of exact quantum mechanical models.In [10], Buck et al. introduced a simple two body potential for describing low lying rotational bands in the 20 Ne and 44 Ti nuclei. It was shown that the poten tial not only determined the positions of the excited levels with sufficient accuracy but also permitted the widths of the states to be estimated and could be used within the optical model. This type of potential was later extended to the rotational states of the 40 Ca nucleus [11]. As was mentioned in [12], the above potential was applicable not only to the alpha particle plus closed shell core systems but also to heavier clus ters and nuclei with particles (holes) in their shell con figuration.Application of the potential from [10] to the 16, 18, 20 O and 20, 22 Ne nuclei resulted in a good descrip tion of low lying rotational bands [13]. The correct value obtained for the theoretical moment of inertia shows that all considered states have very large contri butions from structures like the α + core and do not contain a heavier 6 He nucleus as a cluster. This is valid to a high degree of accuracy even for the 20 O nucleus, for which the theoretical splitting value is slightly higher than the experimental value. This allows the conclusion that the cluster structure manifests itself more globally in light mass and medium mass nuclei with neutron excess [12].Let us consider the known low lying rotational states in nuclei up to titanium, inclusive. Figure 1 shows the parameter o...