When will the spins are parallel and antiparallel?

Answer 1

A hydrogen atom with its electron in the ground state 1sorbital can have proton and electron spins that are eitherparallel or anti parallel which is the lower configuration andwhy? treat the electron as orbiting the proton in a planeperpendicular to the spin of the proton.parallel spinsNeighbouring spinning electrons in which the spins, and

hence the magnetic moments, of the electrons are aligned in

the same direction.

Let us see a look to superconductivity, may be it becomes more clear.

Most, but not all, conductors of electrical current, when cooled sufficiently in the direction of absolute zero (0 oK, -273.15 oC), become superconductors.

The superconducting state itself is one in which there iszeroelectrical resistance and perfect diamagnetism (Of or relating to a substance that is repelled by a magnet.) This means that current flowing through a superconducting circuit does not experience i2R heating (current squared times the

resistance), and the current can flow indefinitely.

How the Cooper pairs are formed is obviously a critical factor in superconductivity. One theory is an electron passing by the crystal lattice of atoms in the conductor distorts the lattice in such a way the next electron is attracted to the lattice distortion. Or instead of the electron-pairing being mediated by lattice vibrations, the interaction of the conduction electrons may be due to charge or electron spin fluctuationsin some electronic subsystem.

The interaction of an electron with the positively charged ions in the crystalline lattice causes a "disturbance", which affects a second electron as it passes by. In certain situations (whatever that means!) the electrons experience an attractive force between them which is stronger than the normal Coulomb repulsion -- and the two electrons form a Cooper pair.

"Electrons of opposite spin and momentum form isotropic or 's-wave' pairs.

A material that is a superconductor contains one vibrational frequency within it, a lot like a laser. The light flows perpetually within the system. No where in the system is there any voltage. You can't hook up a wire here and a wire there to the superconductor and get current to flow in and out of it, because to get current off of the wire, you've got to have a voltage, and yet by definition a superconductor won't allow any voltage. So the material's a perfect insulator, not just a superconductor. But if you resonant frequency tune the wire so that the electrons vibrate at the same frequency as the superconductor, then the electrons will flow on as light, as electron pairs. They will pair up and flow on, because they're seeking the path of least resistance which is the superconductor."

Recent measurements on a class of high Tc superconductors (HTSCs) have shown that Cooper-pairs wavefunction is ad-wave, while in another class,d-wave and s-wave may coexist. Conventional low-Tc superconductors are s-wave superconductors.

"Electrical resistance is zero because the Cooper pair condensate moves as a coherent quantum mechanical entity, which lattice vibrations and impurities cannot disrupt by scattering individual Cooper pairs in the same way they scatter single electrons in a conductor."

unconventional electron-pairing mechanism mediated not by lattice vibrations but by interaction of the conduction electrons with charge or electron

spin (magnetic) fluctuations in some electronic subsystem.

And an example of anti-parallel spin:

Anti-F

erromagnetic Phenomenon in some magnetically ordered materials in which there is an anti-parallel alignment of spins in two interpenetrating structures so that there is no overall bulk spontaneous magnetization.

Answer 2

Spins are parallel when they have the same orientation, resulting in a net spin with a greater magnitude. Spins are antiparallel when they have opposite orientations, canceling each other out, resulting in a net spin with a lesser magnitude.