Published in Chemistry World, 21 Jan 2011
Nine years ago, Russian researchers sparked controversy when they claimed to have separated water into its two spin isomers. Now, chemists in Israel claim to have performed a similar feat using a different method, and suggest the outcome could deliver highly sensitive nuclear magnetic resonance (NMR) experiments.
Water molecules come in two spin isomers: one ‘ortho-water’ with the spins of the constituent hydrogen atoms parallel, and one ‘para-water’ with the hydrogen spins anti-parallel. The two isomers have subtly different properties that become important in diverse fields of science. In astrophysics, for example, the ratio between ortho- and para-water is used to determine temperatures in interstellar space, although the data are hard to interpret – partly because scientists have been unable to study either isomer on its own. […]
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