Doric order proportions. It is suggested that these proportions give the Doric columns a masculine appearance, whereas the more slender Ionic columns appear to represent a more feminine look. This sense of masculinity and femininity was often used to determine which type of column would be used for a particular structure. The most influential, and perhaps the earliest, use of the Doric in Renaissance architecture was in the circular "Tempietto" by Donato Bramante (1502 or later), in the courtyard of San Pietro in Montorio, Rome. Before Greek Revival architecture grew, initially in England, in the 18th century, the Greek or elaborated Roman
Ionic compound and negative ions must be maintained. Instead the material undergoes fracture via cleavage. As the temperature is elevated (usually close to the melting point) a ductile–brittle transition occurs, and plastic flow becomes possible by the motion of dislocations. The compressibility of an ionic compound is strongly determined by its structure, and in particular the coordination number. For example, halides with the caesium chloride structure (coordination number 8) are less compressible than those with the sodium chloride structure (coordination number 6), and less again than those with a coordination number of 4. When ionic compounds dissolve, the individual ions dissociate and