Tue January 03, 2012 By: Onam Singla

dimagnetic substances

Expert Reply
Wed January 04, 2012
Magnetic properties arise from the spin and orbital angular momentum of the electrons contained in a compound. Compounds are diamagnetic when they contain no unpaired electrons. Molecular compounds that contain one or more unpaired electrons are paramagnetic. The magnitude of the paramagnetism is expressed as an effective magnetic moment, ?eff.
  1. Diamagnetism. Every electron is paired with another electron in the same atomic orbital. The moments of the two electrons cancel each other out, so the atom has no net magnetic moment. When placed in a magnetic field the atom becomes magnetically polarized, that is, it develops an induced magnetic moment. The force of the interaction tends to push the atom out of the magnetic field. By convention diamagnetic susceptibility is given a negative sign.
  2. Paramagnetism. At least one electron is not paired with another. The atom has a permanent magnetic moment. When placed into a magnetic field, the atom is attracted into the field. By convention paramagnetic susceptibility is given a positive sign.Irregularities are observed for Chromium, Cr, and Copper, Cu, because the listed
    electronic configurations are energetically
    favoured (i.e. 3d54s1 is more stable than 3d44s2, and 3d104s1 is more stable than
    3d94s1 respectively.).
  3. beacause of this 3d10  it shows diamagnetism.
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