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Nuclear relaxation during the formation of from spin-polarized hydrogen
Phys. Rev. B 48, 15744 – Published 1 December, 1993
DOI: https://doi.org/10.1103/PhysRevB.48.15744
Abstract
We report an NMR study of solid formed by the recombination of doubly polarized atomic hydrogen at a temperature of ∼0.3 K. The molecules are formed in a highly excited ortho state with =-1, thermalize through collisions with the walls of the containment chamber, and form a solid. The solid is essentially pure ortho in the fcc phase, as expected. However, the nuclear polarization is close to zero, in contrast to the value of -1 if there was no relaxation, and +0.034 if the spin temperature was in equilibrium with the surface of the cell. Possible mechanisms for depolarization are discussed, though no plausible explanation for the loss has yet been found.
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