Molecular spin alignment having macro torque effects?

[xerxes73]

Hello,

If a magnetic field aligns the electron or nuclear spins can that have a macro effect of causing torque? So for example if we had a rod and we fixed one end but allowed it to freely rotate and then aligned electron or nuclear spins would that cause the rod to rotate?

Thanks,
Xerxes73

 

[jtbell]

Yes, it's called the Einstein - de Haas effect.

 

[Creator]

And the opposite effect is the Barnett effect, whereby mechanical rotation of a ferromagnetic body on its axis results in magnetization along the rotational axis.

http://prola.aps.org/abstract/PR/v6/i4/p239_1

Creator

 

[xerxes73]

Thanks! I appreciate the info. This led to some interesting reading. -Xerxes73