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Synthesizing any elements in the eighth period using either cold or hot fusion reactions remains a big challenge till date. Quasifission mechanism restricts complete fusion to an indeterminably low evaporation residue (ER) cross section for the superheavy nuclei. Entrance channel parameters of the heavy-ion reaction, fission barrier of compound nucleus, deformation parameters of the projectile and target nuclei, and the kinetic energy of the projectile are mostly responsible in governing the scales of the quasifission. Role of these factors has been examined explicitly by the experimental ER cross sections. Thorough comparisons lead us to infer that the entrance channel criteria contribute much lower extent than the deformation parameters do. The effect of deformation can be categorized into four rules as validated by all the reactions used except one $^{45}_{21}$Sc+$^{249}_{98}$Cf $\rightarrow ^{294}_{119}$Uue. Null result from this reaction is well explained by an improper choice of the projectile energy as shown theoretically by means of a statistical model approach, which is valid for a system having a large nucleon number so as to have intrinsically a high density of excited states. Optimal selection of the beam energy sets another rule. Therefore, these five rules can be treated as the rules of thumb for synthesizing the superheavy elements. Application of the first four rules can enable us to spot primarily a suitable reaction and finally exploitation of the fifth rule chooses the most appropriate reaction at a preferable excited energy to achieve the highest ER cross section for a superheavy element.

We have studied the^54-60Fe–induced fusion reactions to synthesize the superheavy nuclei ^296-302120 by studying the compound nucleus formation probability, survival probability and evaporation residue cross-sections. The comparison of evaporation residue cross section for different targets reveals that evaporation residue cross section is larger for projectile target combination ⁵⁸Fe+²⁴³Pu→³⁰¹120. We have identified the most probable ⁵⁸Fe-induced fusion reactions to synthesize superheavy nuclei ^296-302120. Suggested reactions may be useful to synthesize the superheavy element Z=120.

It was recognized that the magic numbers of nuclei 2, 20, 28, 50, 82 and 126 are predicted to be more stable than the neighbor nuclei. Later on the researchers predicted that the magic numbers for protons are 114, 122, 124 and 164 and the magic numbers for neutrons are 184, 196, 236 and 318. The predicted second generation magic number for proton and neutron comes in the superheavy nuclei region. The superheavy nuclei with magic number of protons/neutrons are [Formula: see text]114, [Formula: see text]114, [Formula: see text]122, [Formula: see text]122, [Formula: see text]124, [Formula: see text]124, [Formula: see text]126 and [Formula: see text]126. All the possible decay modes have been studied by using three different models such as modified generalized liquid drop model, dynamical cluster model and coulomb-proximity potential model. In the second part of this study, we have made detailed investigations to synthesize the above said nuclei using fusion reactions with modified Woods–Saxon potential model. This study also identifies the most possible projectile target combinations for the synthesis of the predicted magic nuclei in the superheavy nuclei region.