Ionic order Ionic order The Ionic order forms one of the three classical orders of classical architecture, the other two canonic orders being the Doric and the Corinthian. There are two lesser orders: the Tuscan (a plainer Doric), and the rich variant of Corinthian called the composite order, both added by 16th-century Italian architectural writers, based on Roman practice. Of the three canonic orders, the Ionic order has the narrowest columns. The Ionic capital is characterized by the use of volutes. The Ionic columns normally stand on a base which separates the shaft of the column from the stylobate or platform; the
Ionic bonding cannot exist, as the proximity of the entities involved in the bonding allows some degree of sharing electron density between them. Therefore, all ionic bonding has some covalent character. Thus, bonding is considered ionic where the ionic character is greater than the covalent character. The larger the difference in electronegativity between the two types of atoms involved in the bonding, the more ionic (polar) it is. Bonds with partially ionic and partially covalent character are called polar covalent bonds. For example, Na–Cl and Mg–O interactions have a few percent covalency, while Si–O bonds are usually ~50% ionic and ~50% covalent.