What Does Diamagnetic Mean in Chemistry

There are different forms of magnetism, a list that includes ferromagnetism, antiferromagnetism, paramagnetism, and diamagnetism. Key Takeaways: Diamagnetism A diamagnetic substance does not have unpaired electrons and is not attracted to a magnetic field.All materials display diamagnetism, but to be diamagnetic, this must be the only contribution to its magnetic behavior.Examples of diamagnetic materials include water, wood, and ammonia. Diamagnetism In chemistry and physics, to be diamagnetic indicates that a substance contains no unpaired electrons  and is not attracted to a magnetic field. Diamagnetism is a quantum mechanical effect that is found in all materials, but for a substance to be termed diamagnetic it must be the only contribution to the matters magnetic effect. A diamagnetic material has a permeability less than that of a vacuum. If the substance is placed in a magnetic field, the direction of its induced magnetism will be opposite to that of iron (a ferromagnetic material), producing a repulsive force. In contrast, ferromagnetic and paramagnetic materials are attracted to magnetic fields. Sebald Justinus Brugmans first observed diamagnetism in 1778, noting antimony and bismuth were repelled by magnets. Michael Faraday coined the terms diamagnetic and diamagnetism to describe the property of repulsion in a magnetic field. Examples Diamagnetism is seen in water, wood, most organic molecules, copper, gold, bismuth, and superconductors. Most living organisms are essentially diamagnetic. NH3 is diamagnetic because all the electrons in NH3 are paired. Usually, diamagnetism is so weak it can only be detected by special instruments.  However, diamagnetism is strong enough in  superconductors  to be readily  apparent. The effect is used to make materials appear to levitate. Another demonstration of diamagnetism may be seen using water and a super magnet (such as a rare earth magnet). If a powerful magnet is covered with a layer of water that is thinner than the diameter of the magnet, the magnetic field repels the water. The minor dimple formed in the water may be viewed by reflection in the waters surface. Sources Jackson, Roland. John Tyndall and the Early History of Diamagnetism. Annals of Science. Kittel, Charles. ,Introduction to Solid State Physics 6th edition. John Wiley Sons.Landau, L.D. Diamagnetismus der Metalle. Zeitschrift fà ¼r Physik A Hadrons and Nuclei.