https://scholarlywiki.org/index.php?action=history&feed=atom&title=Physics%3AQuantum_atoms%2Fspin_isomers_of_hydrogen
Physics:Quantum atoms/spin isomers of hydrogen - Revision history
2026-05-23T14:58:24Z
Revision history for this page on the wiki
MediaWiki 1.44.5
https://scholarlywiki.org/index.php?title=Physics:Quantum_atoms/spin_isomers_of_hydrogen&diff=9154&oldid=prev
Maintenance script: Remove red spin link from spin isomers page
2026-05-23T10:46:02Z
<p>Remove red spin link from spin isomers page</p>
<table style="background-color: #fff; color: #202122;" data-mw="interface">
<col class="diff-marker" />
<col class="diff-content" />
<col class="diff-marker" />
<col class="diff-content" />
<tr class="diff-title" lang="en">
<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">← Older revision</td>
<td colspan="2" style="background-color: #fff; color: #202122; text-align: center;">Revision as of 10:46, 23 May 2026</td>
</tr><tr><td colspan="2" class="diff-lineno" id="mw-diff-left-l18">Line 18:</td>
<td colspan="2" class="diff-lineno">Line 18:</td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>* [[Physics:Quantum atoms/isotopes of hydrogen]]</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>* [[Physics:Quantum atoms/isotopes of hydrogen]]</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>* [[Physics:Quantum Molecular orbital theory]]</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>* [[Physics:Quantum Molecular orbital theory]]</div></td></tr>
<tr><td class="diff-marker" data-marker="−"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #ffe49c; vertical-align: top; white-space: pre-wrap;"><div>* <del style="font-weight: bold; text-decoration: none;">[[Physics:Quantum </del>spin<del style="font-weight: bold; text-decoration: none;">]]</del></div></td><td class="diff-marker" data-marker="+"></td><td style="color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #a3d3ff; vertical-align: top; white-space: pre-wrap;"><div>* <ins style="font-weight: bold; text-decoration: none;">nuclear </ins>spin <ins style="font-weight: bold; text-decoration: none;">states</ins></div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>* [[Physics:Quantum fermion]]</div></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><div>* [[Physics:Quantum fermion]]</div></td></tr>
<tr><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br></td><td class="diff-marker"></td><td style="background-color: #f8f9fa; color: #202122; font-size: 88%; border-style: solid; border-width: 1px 1px 1px 4px; border-radius: 0.33em; border-color: #eaecf0; vertical-align: top; white-space: pre-wrap;"><br></td></tr>
<!-- diff cache key my_wiki:diff:1.41:old-9140:rev-9154:php=table -->
</table>
Maintenance script
https://scholarlywiki.org/index.php?title=Physics:Quantum_atoms/spin_isomers_of_hydrogen&diff=9140&oldid=prev
Maintenance script: Create Quantum Collection spin isomers of hydrogen page
2026-05-23T10:39:13Z
<p>Create Quantum Collection spin isomers of hydrogen page</p>
<p><b>New page</b></p><div>{{Short description|Nuclear spin isomers of molecular hydrogen}}<br />
{{Quantum matter backlink|Atoms}}<br />
<br />
'''Spin isomers of hydrogen''' are forms of molecular hydrogen that differ in the relative nuclear spin orientation of the two protons in <math>\mathrm{H}_2</math>. The two main forms are '''orthohydrogen''' and '''parahydrogen'''.<br />
<br />
== Ortho and para hydrogen ==<br />
In '''orthohydrogen''', the two proton spins are parallel and the total nuclear spin is <math>I=1</math>. In '''parahydrogen''', the two proton spins are antiparallel and the total nuclear spin is <math>I=0</math>.<br />
<br />
Because protons are fermions, the total molecular wavefunction must have the proper exchange symmetry. This links the nuclear spin state to the allowed rotational states of the molecule.<br />
<br />
== Quantum significance ==<br />
The ortho and para forms have different rotational energy level populations and different low-temperature behavior. At room temperature hydrogen is mostly orthohydrogen, while at very low temperature the para form is energetically favored.<br />
<br />
Spin isomers are important in cryogenics, molecular spectroscopy, nuclear spin physics, and precision studies of hydrogen molecules.<br />
<br />
== Related pages ==<br />
* [[Physics:Quantum atoms/hydrogen]]<br />
* [[Physics:Quantum atoms/isotopes of hydrogen]]<br />
* [[Physics:Quantum Molecular orbital theory]]<br />
* [[Physics:Quantum spin]]<br />
* [[Physics:Quantum fermion]]<br />
<br />
== References ==<br />
{{reflist|3}}<br />
* {{Cite web |title=Ortho-hydrogen and para-hydrogen |url=https://www.britannica.com/science/hydrogen/Ortho-hydrogen-and-para-hydrogen |website=Encyclopaedia Britannica |access-date=2026-05-23}}<br />
* {{Cite book |last=Silvera |first=Isaac F. |title=The solid molecular hydrogens in the condensed phase: Fundamentals and static properties |journal=Reviews of Modern Physics |year=1980 |volume=52 |issue=2 |pages=393-452 |doi=10.1103/RevModPhys.52.393}}<br />
<br />
{{Author|Harold Foppele}}</div>
Maintenance script