By Sunil Bhardwaj

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The capture of neutron by Uranium does not necessary lead to the fission. (_{ 92 }^{ 238 }U) has a small capture cross-section for low energy neutrons. The importance of capture of neutron by (_{ 92 }^{ 238 }U) is that it leads to the formation of new elements known as Transuranium (or) Transuranic elements because these new elements have the position in the periodic table after Uranium.

In 1934, Fermi suggested the production of the elements having the atomic no. greater than Uranium, i.e. 92.

When( _{ 92 }^{ 238 }U) is bombarded with neutrons. $$ _{ 92 }^{ 238 }U + _{ 0 }^{ 1 }n longrightarrow _{ 92 }^{ 239 }U (excited) longrightarrow _{ 92 }^{ 239 }U + gamma -rays $$ ( _{ 92 }^{ 239 }U) undergo the ({ eta }^{ - }) emission forming Np of atomic no 93 Np further undergo ({ eta }^{ - }) emission forming Pu which will give Am. $$ _{ 92 }^{ 239 }U underset { -{ eta }^{ - } }{ longrightarrow } _{ 93 }^{ 239 }Np underset { -{ eta }^{ - } }{ longrightarrow } _{ 94 }^{ 239 }Pu underset { -{ eta }^{ - } }{ longrightarrow } _{ 95 }^{ 239 }Am underset { -{ eta }^{ - } }{ longrightarrow } _{ 96 }^{ 239 }Cm underset { -{ eta }^{ - } }{ longrightarrow } _{ 97 }^{ 239 }Bk $$ All these elements have the position in the periodic Table after Uranium, So these elements are known as Transuranic Or Transuranium elements.