Ancient Greek temple three steps, the "crepidoma". The uppermost level of the "crepidoma" provides the surface on which the columns and walls are placed; it is called stylobate. Placed on the stylobate are the vertical column shafts, tapering towards the top. They are normally made of several separately cut column drums. Depending on the architectural order, a different number of flutings are cut into the column shaft: Doric columns have 18 to 20 flutings, Ionic and Corinthian ones normally have 24. Early Ionic columns had up to 48 flutings. While Doric columns stand directly on the stylobate, Ionic and Corinthian ones possess a
Perovskite (structure) properties of interest to materials science among perovskites include superconductivity, magnetoresistance, ionic conductivity, and a multitude of dielectric properties, which are of great importance in microelectronics and telecommunication. Because of the flexibility of bond angles inherent in the perovskite structure there are many different types of distortions which can occur from the ideal structure. These include tilting of the octahedra, displacements of the cations out of the centers of their coordination polyhedra, and distortions of the octahedra driven by electronic factors (Jahn-Teller distortions). Synthetic perovskites have been identified as possible inexpensive base materials for high-efficiency commercial photovoltaics – they showed