List transition series

Transition metal, any of various chemical elements that have valence electrons—i.e., electrons that can participate in the formation of chemical bonds—in two shells instead of only one. While the term transition has no particular chemical significance, it is a convenient name by which to distinguish the similarity of the atomic structures and resulting properties of the elements so designated. They occupy the middle portions of the long periods of the periodic table of elements between the groups on the left-hand side and the groups on the right. Specifically, they form Groups 3 (IIIb) through 12 (IIb). 

Some of the more well-known transitional metals include titanium, iron, manganese, nickel, copper, cobalt, silver, mercury and gold. Three of the most noteworthy elements are iron, cobalt and nickel as they are only elements known to produce a magnetic field.