Researchers successfully isolate two molecular forms of water
July 20, 2018
Water molecules are ubiquitous, vital, and may have the world’s most well-known chemical formula (H₂O). The properties of water are quite unique; its solid state is less dense than its liquid state, raising pressure lowers its melting point, and it exists as a liquid at room temperature despite low molecular mass. Even more unique is the water molecule’s ability to exist as two distinct nuclear configurations called spin isomers.
The two spin isomers of water molecules differ based on the direction of the nuclear spin of the two hydrogen nuclei. If the two hydrogen nuclei have parallel spins, the molecule is known as ortho-water. If the two hydrogen nuclei have opposite spins, the molecule is known as para-water. Water at room temperature always contains a mix of these two spin isomers and, until recently, it has been nearly impossible to study them separately.
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