In classical mechanics, this phenomenon can be modelled via the Langevin function. For 10 points each:
[10e] Name this form of magnetism exhibited by materials that are attracted by an external magnetic field but do not retain magnetism when the field is removed. This form of magnetism is contrasted with diamagnetism and ferromagnetism.
ANSWER: paramagnetism [or word forms like paramagnetic]
[10h] The quantum theoretical analogue of the Langevin function is named for this scientist. In crystals, this scientist names cells in reciprocal space that are used to calculate electronic band structure.
ANSWER: Léon Nicolas Brillouin (“bree-WANN”) [accept first Brillouin zone]
[10m] Expanding the Langevin function to first-order in the weak field limit recovers this law, which states that magnetic susceptibility is inversely proportional to temperature.
ANSWER: Curie’s law [or Curie–Weiss law]
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