Magnetic potential energy

In the presence of an external magnetic induction B this dipole Pm has a potential energy given by the laws of classical electromagnetism as... 

Atomic and molecular magnetic dipoles have to obey the angular momentum laws of quantum mechanics, since they are proportional to angular momenta. Each dipole can therefore make just a number of orientations with an applied magnetic induction B. Each allowed orientation corresponds to a different potential energy, and absorption of a photon with suitable energy may cause a change in orientation. 

It is clear that nonconfigurational factors are of great importance in the formation of solid and liquid metal solutions. Leaving aside the problem of magnetic contributions, the vibrational contributions are not understood in such a way that they may be embodied in a statistical treatment of metallic solutions. It would be helpful to have measurements both of ACP and A a. (where a is the thermal expansion coefficient) for the solution process as a function of temperature in order to have an idea of the relative importance of changes in the harmonic and the anharmonic terms in the potential energy of the lattice. 

Potential energies then arise from forces acting between the parts of the system. The nature of these forces (gravity, magnetic forces, electrical forces, molecular and atomic forces) is very obscure. 

Silver atoms, being paramagnetic, have a magnetic moment M. In a magnetic field B, the potential energy Fof each atom is... 

The potential energy V of an atom with a magnetic moment M in a magnetic field B is... 

When a magnetic field B is applied to a hydrogen-like atom with magnetic moment M, the resulting potential energy V is given by the classical expression... 

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