گشتاور ِ مغناتیسی ِ اسپین gaštâvar-e meqnâtisi-ye espin (#)
*Fr.: moment magnétique de spin*
The magnetic moment associated with the → *spin angular momentum*
of a charged particle. The direction of the magnetic moment is opposite to the direction
of the angular momentum. The magnitude of the magnetic moment is given by:
**μ** = -*g(q / 2m)***J**, where *q* is the charge, *m* is the mass,
and **J** the angular momentum. The parameter *g* is a characteristic of the
state of the atom. It would be 1 for a pure orbital moment, or 2 for a spin moment, or some
other number in between for a complicated system like an atom. The quantity
in the parenthesis for the electron is the → *Bohr magneton*.
The electron spin magnetic moment is important in the → *spin-orbit*
interaction which splits atomic energy levels and gives rise to
→ *fine structure* in the spectra of atoms.
It is also a factor in the interaction of atom with external fields,
→ *Zeeman effect*. → *spin*; → *magnetic moment*. |