Exchange Interactions Between Localized Electron Magnetic Moments
Quantum mechanical particles are classified as bosons or fermions. The spin-statistics theorem of quantum field theory demands that all particles with half-integer spin behave as fermions and all particles with integer spin behave as bosons. Multiple bosons may occupy the same quantum state; by the Pauli exclusion principle, however, no two fermions can occupy the same state. Since electrons have spin 1/2, they are fermions. This means that the overall wave function of a system must be antisymmetric when two electrons are exchanged, i.e. interchanged with respect to both spatial and spin coordinates. First, however, exchange will be explained with the neglect of spin.
Read more about this topic: Exchange Interaction
Famous quotes containing the words exchange, interactions, magnetic and/or moments:
“I sometimes feel a great ennui, profound emptiness, doubts which sneer in my face in the midst of the most spontaneous satisfactions. Well, I would not exchange all that for anything, because it seems to me, in my conscience, that I am doing my duty, that I am obeying a superior fatality, that I am following the Good and that I am in the Right.”
—Gustave Flaubert (1821–1880)
“In child rearing it would unquestionably be easier if a child were to do something because we say so. The authoritarian method does expedite things, but it does not produce independent functioning. If a child has not mastered the underlying principles of human interactions and merely conforms out of coercion or conditioning, he has no tools to use, no resources to apply in the next situation that confronts him.”
—Elaine Heffner (20th century)
“We are in great haste to construct a magnetic telegraph from Maine to Texas; but Maine and Texas, it may be, have nothing important to communicate.”
—Henry David Thoreau (1817–1862)
“The government does not concern me much, and I shall bestow the fewest possible thoughts on it. It is not many moments that I live under a government, even in this world. If a man is thought- free, fancy-free, imagination-free ... unwise rulers or reformers cannot fatally interrupt him.”
—Henry David Thoreau (1817–1862)