In reply to Bob Cook's message of Thu, 12 Nov 2015 21:50:05 -0800: Hi, [snip] >I would note that the total angular momentum of a system includes its electron >orbital angular momentum and the intrinsic angular momentum of the electrons >and the particles that make up a the nuclei of the system. The total angular >momentum can only change in discrete small quanta of h/2pi which means that >each component, the orbital and the intrinsic angular momentum can only >change in increments of h/2pi.
This is because h/2pi is the angular momentum of a photon, which is either absorbed or emitted, and conservation of angular momentum requires that the sum of the angular momentum of the system and that of the photon remain constant. Regards, Robin van Spaandonk http://rvanspaa.freehostia.com/project.html
