Ionic order a version of such a perfectly four-sided Ionic capital; Scamozzi's version became so much the standard, that when a Greek Ionic order was eventually reintroduced, in the later 18th century Greek Revival, it conveyed an air of archaic freshness and primitive, perhaps even republican, vitality. The Ionic column is always more slender than the Doric; therefore, it always has a base: Ionic columns are eight and nine column-diameters tall, and even more in the Antebellum colonnades of late American Greek revival plantation houses. Ionic columns are most often fluted. After a little early experimentation, the number of hollow flutes in
Ionic radius radii. The relation between soft-sphere ionic radii, formula_2 and formula_3, and formula_1, is given by formula_5, where formula_6 is an exponent that varies with the type of crystal structure. In the hard-sphere model, formula_6 would be 1, giving formula_8. In the soft-sphere model, formula_6 has a value between 1 and 2. For example, for crystals of group 1 halides with the sodium chloride structure, a value of 1.6667 gives good agreement with experiment. Some soft-sphere ionic radii are in the table. These radii are larger than the crystal radii given above (Li, 90 pm; Cl, 167 pm). Inter-ionic separations calculated