Berry Mechanism - Berry Mechanism in Square Pyramidal Structure

Berry Mechanism in Square Pyramidal Structure

The Berry mechanism in square pyramidal molecules (such as IF5) is somewhat like the inverse of the mechanism in bipyramidal molecules. Starting at the "transition phase" of bipyramidal pseudorotation, one pair of fluorines scissors back and forth with a third fluorine, causing the molecule to vibrate. Unlike with pseudorotation in bipyramidal molecules, the atoms and ligands which are not actively vibrating in the "scissor" motion are still participating in the process of pseudorotation; they make general adjustment based on the movement of the actively vibrating atoms and ligands. However, this geometry requires a significant amount of energy to occur of about 26.7 kcal/mol.

Read more about this topic:  Berry Mechanism

Famous quotes containing the words berry, mechanism, square and/or structure:

    Being a parent is a form of leadership. . . . Parents make a mistake, along with leaders of organizations, when they are unwilling to recognize the power inherent in the positions they occupy and when they are unwilling to use this power. . . . I do not mean a figure who is irrational, autocratic, or sadistic. I mean leaders who have the strength of character to stand up for what they believe.
    —Abraham Zaleznik. In Support of Families, ed. Michael W. Yogman and T. Berry Brazelton, ch. 8 (1986)

    The law isn’t justice. It’s a very imperfect mechanism. If you press exactly the right buttons and are also lucky, justice may show up in the answer. A mechanism is all the law was ever intended to be.
    Raymond Chandler (1888–1959)

    If the physicians had not their cassocks and their mules, if the doctors had not their square caps and their robes four times too wide, they would never had duped the world, which cannot resist so original an appearance.
    Blaise Pascal (1623–1662)

    Science is intimately integrated with the whole social structure and cultural tradition. They mutually support one other—only in certain types of society can science flourish, and conversely without a continuous and healthy development and application of science such a society cannot function properly.
    Talcott Parsons (1902–1979)