magnetic properties of the elements
The following descriptions and definitions refer to the accompanying chart [sic] called, “Magnetic Properties of the Elements,” which was compiled in May 2001.
Definition of Terms
Science uses the terms, ferromagnetic, paramagnetic, and diamagnetic to describe the magnetic properties of elements.
I. Ferromagnetism in Elements
This property is associated with the element iron (Fe), hence the reference to “ferro.” Ferrous materials are known for their strong magnetic fields and high magnetic susceptibility.
II. Paramagnetism in Elements
This magnetic property is produced by the phenomenon of electron paramagnetic resonance, where an external magnetic field causes electrons in an atom to undergo resonant absorption (and emission) of microwave energy. As is the case with nuclear resonance, the frequency of electron paramagnetic resonance varies directly with the strength of the applied magnetic field. Paramagnetism does not show up unless the particular atom with this property comes into contact with another magnetic field, either from an electro-magnet, or a magnetic made from a ferromagnetic material such as iron.
III. Diamagnetism in Elements
An atom is diamagnetic when it cannot be magnetized to any significant degree. It is also related to the phenomenon of conductivity in that some diamagnetic elements, such as the noble metals (copper, silver, gold), are good conductors. Originally it was thought that diamagnetic materials had no magnetic properties. After the discovery of superconductors, however, it became apparent that magnetism did develop in these materials, but differently than in the magnetic materials.
Whenever diamagnetic elements are exposed to a magnetic pole (north or south), they take on its polarity. In magnetic elements, the exposure to a particular magnetic pole always produces its opposite. The “like pole” of these materials keeps their magnetic fields inside the boundaries of their material structures (inside their atomic structures), making them difficult to detect.
Magnetic Properties of Groups of Elements in the Periodic Chart
1. Group 1 elements: Paramagnetic
2. Group 2 elements: Paramagnetic to ferromagnetic
3. Group 3 elements: Ferromagnetic
4. Group 4 elements: Diamagnetic
5. The Group 5 elements are those with magnetic properties that do not fit into the normal pattern. There are three subgroups within this classification.
A. The Group 5A superconductor dopant elements
The relationship between the Group 5A elements and superconductive materials is as follows. Group 5A elements have a “+2″ valence. Normally, the two valence electrons occupy the same orbit, and have different spins. When a potential is placed across a Type II superconductor, the electrons that compose the resulting current move into (rather than over) the material. Some of these conducting electrons move into (and then out of) lattice vacancies where atoms and valence electrons are missing. Here they pair up with single electrons and take on their spin, creating, in effect, “like spin” electron pairs.
According to the Pauli Exclusion Principle, no two electrons in the same orbit can have the same spin. If they do, then one of them must revert to its original spin, leave the orbit to another orbit, or leave the atom entirely. Two of these processes require the addition of energy to the electron. The third (reverting to original state) does not. The bonding structure of the lattice that holds the atoms that make up the superconductor does not allow electrons to change spin. As a result, one of the valence electrons leaves orbit without the addition of energy. This is not allowed under quantum theory, where energy is normally required for an atomic transition to take place.
Superconductivity violates Ohm’s Law of electrical resistance, quantum theory, thermodynamics, and conservation of energy. For laws and reasons of its own, it occurs when a specific thermodynamic state (temperature) is reached, and electrons are suddenly allowed to move, virtually without electrical resistance, through its lattice.
B. The Group 5B dual state elements
This is a special category of elements whose magnetism is capable of being reversed from diamagnetic to weakly magnetic. These are quadrivalent elements, with the potential of either adding or subtracting up to four valence electrons, giving them either a “+4″ or a “-4″ valence. Currently, only tin (Sn) is listed as weakly magnetic. However, when the other elements in the group (C, Si, Ge, Pb) occur in compounds, they too can be magnetized weakly.
C. The single Group 5C element is oxygen
Oxygen’s property of ferromagnetism is completely at odds with the diamagnetism of the Group 4 elements that surround it. Its strong magnetism is even more anomalous when its even-number (-2) valence is taken into consideration. This valence should make it diamagnetic, as it does in the element sulfur, which has the same valence, and lies immediately below it in the periodic chart.