Spin | Nuclear Structure, Electron Configurations & Magnetic Moments

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class="drawer d-flex flex-column open"> <div class="left-rail-section-content"> <div class="topic-left-rail-header text-truncate bg-gray-50 position-relative text-right d-flex align-items-center"> <div class="tlr-title px-20 py-15 text-left"> <em class="material-icons text-gray-400 d-lg-none" data-icon="toc"></em> <a class="font-serif font-weight-bold text-black link-blue" href="https://www.britannica.com/science/spin-atomic-physics">spin</a> </div> <button aria-label="Close" class="js-sections-close-button btn-link btn-sm btn d-lg-none position-absolute top-0 p-10 right-0" > <em class="material-icons font-26" data-icon="close"></em> </button> </div> <div class="section-content pl-10 pr-20 pl-sm-50 pr-sm-60 pl-lg-5 pr-lg-10 pt-10 pt-lg-0 bg-gray-50 clear-catfish-ad"> <div class="toc mb-20"> <div class="font-serif font-14 font-weight-bold mx-15 mb-15 mt-20"> Table of Contents </div> <span class="toc-extra-link selected link-gray-900 mt-15"> Introduction </span> <a class="toc-extra-link link-gray-900" href="https://www.britannica.com/science/spin-atomic-physics/additional-info">References & Edit History</a> <a class="toc-extra-link link-gray-900" href="/facts/spin-atomic-physics">Quick Facts & Related Topics</a> </div> <div class="mb-30 tlr-related-questions"> <div class="text-gray-900 p-5 pb-0 font-serif font-14 font-weight-bold mx-10 mb-15"> Related Questions </div> <ul> <li class="link-gray-900 mb-15"><a class="" href="/question/How-is-the-atomic-number-of-an-atom-defined">How is the atomic number of an atom defined?</a> </li> </ul> </div> <div class="mb-30 tlr-discover"> <div class="text-gray-900 p-5 font-serif font-14 font-weight-bold mx-10 mb-10"> Discover </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/list/10-of-the-worlds-most-dangerous-fish"> <img loading="lazy" src="https://cdn.britannica.com/96/173996-131-3DDAD81A/Fish-Lionfish-Lion-fish-Turkey-fish-Red-lionfish.jpg?w=200&h=200&c=crop" alt="Fish. Lionfish. Lion-fish. Turkey fish. Fire-fish. Red lionfish. Pterois volitans. Venomous fin spines. Coral reefs. Underwater. Ocean. Red lionfish swims by seaweed." width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/list/10-of-the-worlds-most-dangerous-fish" >10 of the World’s Most Dangerous Fish</a> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/story/nikola-teslas-weird-obsession-with-pigeons"> <img loading="lazy" src="https://cdn.britannica.com/13/173513-131-C6E1BD52/mourning-dove-North-America.jpg?w=200&h=200&c=crop" alt="bird. mourning dove. pigeon and dove. 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Homepage 2010, arts and entertainment, history and society" width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/list/the-10-greatest-basketball-players-of-all-time" >The 10 Greatest Basketball Players of All Time</a> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/list/6-of-the-worlds-deadliest-natural-disasters"> <img loading="lazy" src="https://cdn.britannica.com/16/234616-131-50959175/Damage-Balakot-Pakistan-due-to-earthquake-October-8-2005-Kashmir.jpg?w=200&h=200&c=crop" alt="In this aerial photo, structures are damaged and destroyed October 15, 2005 in Balakot, Pakistan. It is estimated that 90% of the city of Balakot was leveled by the earthquake. The death toll in the 7.6 magnitude earthquake that struck northern Pakistan on October 8, 2005 is believed to be 38,000 with at least 1,300 more dead in Indian Kashmir. SEE CONTENT NOTES." width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/list/6-of-the-worlds-deadliest-natural-disasters" >6 of the World’s Deadliest Natural Disasters</a> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/list/6-deadliest-earthquakes"> <img loading="lazy" src="https://cdn.britannica.com/41/166941-131-E27FD3A6/Yingxiu-school-China-Sichuan-earthquake-May-2008.jpg?w=200&h=200&c=crop" alt="earthquake. Heavily damaged school in the town of Yingxiu after a major earthquake struck China's Sichuan Province on May 12, 2008." width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/list/6-deadliest-earthquakes" >The 6 Deadliest Earthquakes Since 1950</a> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/story/the-lost-colony-of-roanoke"> <img loading="lazy" src="https://cdn.britannica.com/39/191439-131-59FE0A72/John-White-word-tree-CROATOAN-Roanoke-Island-1590.jpg?w=200&h=200&c=crop" alt="The Lost Colony of Roanoke, North Carolina, where 115 people mysteriously disappeared c. 1590. John White discovers the word Croatoan carved onto a tree upon his return to the deserted Roanoke Colony in 1590" width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/story/the-lost-colony-of-roanoke" >The Lost Colony of Roanoke</a> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/story/which-waters-do-you-pass-through-when-you-sail-the-seven-seas"> <img loading="lazy" src="https://cdn.britannica.com/97/196697-131-0155C802/Sailboat-landscape.jpg?w=200&h=200&c=crop" alt="Sailboat against a beautiful landscape" width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" 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For electrons, neutrons, and protons, the multiple is 0.5; pions have zero spin. The total angular momentum of nuclei more complex than the proton is the vector sum of the orbital angular momenta and <a class="md-dictionary-link md-dictionary-tt-off mw" data-term="intrinsic" href="https://www.merriam-webster.com/dictionary/intrinsic" data-type="MW">intrinsic</a> spins of the <a class="md-dictionary-link md-dictionary-tt-off mw" data-term="constituent" href="https://www.merriam-webster.com/dictionary/constituent" data-type="MW">constituent</a> nucleons. For nuclei of even <a href="https://www.britannica.com/science/mass-number" class="md-crosslink autoxref " data-show-preview="true">mass number</a>, the multiple is an integer; for those of odd mass number, the multiple is a half-integer. All nuclei with even numbers of neutrons and protons have spin zero in their ground states.</p><span class="marker MOD1 mod-inline"></span></section> <span class="md-signature font-12">This article was most recently revised and updated by <a href="/editor/William-L-Hosch/6481">William L. 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