Diamagnetism
Weak repulsion from a magnetic field, shown by substances in which all electrons are spin-paired.
Formula / equation
μ = 0 BM
Unit
BM
In depth
An applied field induces electron currents that oppose it, producing a small negative susceptibility. Diamagnetism is present in all matter but is masked whenever unpaired electrons make a sample paramagnetic. Its detection therefore proves that every electron in the species is paired.
Examples in the real world
N₂, water and benzene are all diamagnetic; the low-spin complex [Fe(CN)₆]⁴⁻ is diamagnetic while [Fe(H₂O)₆]²⁺ is not.