Metallic Bond - Strength of The Bond

Strength of The Bond

The atoms in metals have a strong attractive force between them. Much energy is required to overcome it. Therefore, metals often have high boiling points, with tungsten (5828 K) being extremely high. A remarkable exception are the elements of the zinc group: Zn, Cd, and Hg. Their electron configuration ends in ...ns2 and this comes to resemble a noble gas configuration like that of helium more and more when going down in the periodic table because the energy distance to the empty np orbitals becomes larger. These metals are therefore relatively volatile, and are avoided in ultra-high vacuum systems.

Otherwise, metallic bonding can be very strong, even in molten metals, such as Gallium. Even though gallium will melt from the heat of one's hand just above room temperature, its boiling point is not far from that of copper. Molten gallium is therefore a very nonvolatile liquid thanks to its strong metallic bonding.

The latter also exemplifies that metallic bonding due to its delocalization in all directions is often not very particular about the directionality of the bonding. There is typically a preference for close packing of the atoms, such as face or body centered cubic arrangements, but in the case of liquid gallium the stacking is not regular, at least not at long range and bond angles are easily changed.

Given high enough cooling rates and appropriate alloy composition, metallic bonding can occur even in glasses with an amorphous structure.

Much biochemistry is mediated by the weak interaction of metal ions and biomolecules. Such interactions and their associated conformational change has been measured using dual polarisation interferometry.

Read more about this topic:  Metallic Bond

Famous quotes containing the words strength of, strength and/or bond:

    Sprung from the West,
    He drank the valorous youth of a new world.
    The strength of virgin forests braced his mind,
    The hush of spacious prairies stilled his soul.
    His words were oaks in acorns; and his thoughts
    Were roots that firmly gript the granite truth.
    Edwin Markham (1852–1940)

    The same strength of character which helps a man resist love, helps to make it more violent and lasting too. People of unsettled minds are always driven about with passions, but never absolutely filled with any.
    François, Duc De La Rochefoucauld (1613–1680)

    Don’t go on a man’s bond in public, nor guarantee his debts in private.
    Chinese proverb.