Because my question includes images I link the question from Physics Stack Exchange http://physics.stackexchange.com/questions/139460/outcome-from-this-experiment-with-solid-hydrogen
Are you interested in trying it out?
This experiment is not possible with hydrogen.
If you cool down the hydrogen to get the solid state you will produce so-called para-hydrogen with antiparallel proton spins only (anti-symmetric combination of both anti-parallel states). When you try now to polarize the solid hydrogen block in different ways you will transfer energy to the hydrogen during the transition from para- to ortho-hydrogen (with parallel proton spins). The solid hydrogen will be melted in this process. Therefore, solid ortho-hydrogen with parallel nuclear spins is not posible to my knowledge.
You might try the experiment with deuterium. Here the S=2 state with parallel deuteron spins is the ground state and can be populated at very low temperatures.
Thanks for the tip (I'll do research about it).
After reading second time your answer I realize that I haven't presented my experiment clear enough. I don't mind para-hydrogen state, it's just fine. My goal is to have two lattices where those protons can contact (when lattices are put together) in transverse spin-spin fashion. I was hoping that those para-hydrogen diatomic molecules could be polarized to meet the requirement presented in those pictures.
I am wondering.. the triplet ortho to singlet para transition is a very slow process, right? As one cools down n-H2 with 75% o-H2, would there be sufficient number of o-H2 in the solid hydrogen for long enough to study its structure or thermal properties?
Dear Subramanian,
In solid Hydrogen you will not find o-H2 in first order. Yes, it is a slow process, but the energy difference is enough to heat up the H2 at very low temperatures. And when you get a lower temperature of the hydrogen the o- to para-H2 transitions speed up. In cryo-physics it is well known that the production of solid hydrogen is quiet difficult, because you have to overcome the so-called "slush-ice" phase of the hydrogen at about 30 K.
One exception might be possible: If you add a very(!) strong magnetic field then you will split the o-H2 states into the substates and the S=1, m_S=-1 state (Both proton spins antiparallel to the external field) will cross the binding energy of the para-H2 (similar to the Breit-Rabi-Diagram). In this case a population of this state might be possible.
Dear Dr. Engles,
Thank you very much for the explanation. To be honest, while I have experimentally studied phenomenon at cryogenic temperatures, solid hydrogen is not my expertise. I will continue to develop an understanding of the topic.
There is now a paper available describing my experiment suggestion. Kind of big title on it.
After thinking about my setup (while keeping in mind received feedback) it might be better to use ortho-hydrogen instead of para-hydrogen. Gaining the wanted spin orientation is much easier with ortho-hydrogen.
I updated the paper accordingly.
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