Ionic order edifices antiques de Rome" (Paris 1682). 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
Ionic radius ionic radius values are sufficiently transferable to allow periodic trends to be recognized. As with other types of atomic radius, ionic radii increase on descending a group. Ionic size (for the same ion) also increases with increasing coordination number, and an ion in a high-spin state will be larger than the same ion in a low-spin state. In general, ionic radius decreases with increasing positive charge and increases with increasing negative charge. An "anomalous" ionic radius in a crystal is often a sign of significant covalent character in the bonding. No bond is "completely" ionic, and some supposedly "ionic" compounds,