Transition elements are characterized by having the "s" orbital of the N shell (4 or 5) filled, the "p" empty, and the "d" orbital of the N-1 shell half-full. Hover your mouse over the two rows of transition elements and check it out
The treatment of these molecules exceeds the objective of this course. However, on the right you have a molecular model of the potassium ferrocyanide complex K4Fe(CN)6 (the four potassium atoms have been omitted). This molecule is widely used as a blue pigment for inks and paints and as an oxidizing product. Iron (Fe) contributes 6 electrons (of the eight it initially has, it has lost two before forming the molecule) and each cyanide group (CN) contributes 2 electrons. In total, 18 electrons. Iron is in the center, linked by single bonds to six carbons in gray. Each carbon is linked by a triple bond to a nitrogen in blue.
