Forum for Science, Industry and Business

Sponsored by:     3M 
Search our Site:


Sorting Water Molecules


Separation of para and ortho water

Not all water is equal—at least not at the molecular level. There are two versions of the water molecule, para and ortho water, in which the spin states of the hydrogen nuclei are different. In the journal Angewandte Chemie, German researchers have now reported the successful separation of the two forms.

Spin is a quantum mechanical value that can be visualized as the intrinsic angular momentum of a particle rotating around its own axis. A hydrogen nucleus (proton) can adopt two different states, comparable to rotation clockwise and counterclockwise.

In the case of water, the nuclear spins of the two—indistinguishable—protons can be combined in four different ways: one antisymmetric and three symmetric wavefunctions. Water adopting the antisymmetric wavefunction is called para water, whereas water adopting one of the symmetric ones is called ortho water. Because switching from one state to the other is “forbidden” due to quantum-mechanical symmetry rules, the two spin isomers cannot interconvert without external influences such as collisions.

A team at the Center for Free Electron Laser Science (DESY and University of Hamburg) led by Jochen Küpper and Daniel Horke has now successfully separated the two spin isomers and prepared isolated, highly pure samples of para and ortho water.

The challenge was to “freeze” the spin states by diluting single water molecules to such an extent that they could no longer collide with each other. To achieve this, the researchers use a noble gas high-pressure chamber charged with one droplet of water. When the chamber’s pulse valve is opened, the mixture shoots into a vacuum chamber at supersonic speeds, cooling rapidly due to the extremely fast expansion. This results in a focused beam of very cold water molecules that are so far from each other that they cannot induce a spin flip in each other.

For the separation, the researchers made use of the fact that para and ortho water molecules do not have the same quantum states. In a strong inhomogeneous electric field, the accelerated water molecules are deflected from their flight path by a different amount depending on their quantum state.

Possible applications for spin-pure water extend to many fields. Astrophysicists have determined that the ratio of ortho water to para water in interstellar ice is different from what is expected. Spin-pure water could enable revealing laboratory experiments. Techniques such as nuclear magnetic resonance spectroscopy (NMR) could benefit as their sensitivity could be increased by the use of para water in the hydration shells of proteins, improving the determination of their structure.

About the Author

Dr. Jochen Küpper is a team leader at DESY and Professor of Experimental Physics at the University of Hamburg. His research field comprises molecular physics and physical chemistry, focusing on the interconnection of structure, dynamics, and function of molecules. He already received several awards, including the Nernst-Haber-Bodenstein Award of the German Bunsen Society in 2009 and a Consolidator Grant „COMOTION“ of the European Research Council in 2013.

Author: Jochen Küpper, DESY, Hamburg (Germany),

Title: Separating Para and Ortho Water

Angewandte Chemie International Edition

Permalink to the original article:

Jochen Küpper | Angewandte Chemie

More articles from Life Sciences:

nachricht First time-lapse footage of cell activity during limb regeneration
25.10.2016 | eLife

nachricht Phenotype at the push of a button
25.10.2016 | Institut für Pflanzenbiochemie

All articles from Life Sciences >>>

The most recent press releases about innovation >>>

Die letzten 5 Focus-News des innovations-reports im Überblick:

Im Focus: Etching Microstructures with Lasers

Ultrafast lasers have introduced new possibilities in engraving ultrafine structures, and scientists are now also investigating how to use them to etch microstructures into thin glass. There are possible applications in analytics (lab on a chip) and especially in electronics and the consumer sector, where great interest has been shown.

This new method was born of a surprising phenomenon: irradiating glass in a particular way with an ultrafast laser has the effect of making the glass up to a...

Im Focus: Light-driven atomic rotations excite magnetic waves

Terahertz excitation of selected crystal vibrations leads to an effective magnetic field that drives coherent spin motion

Controlling functional properties by light is one of the grand goals in modern condensed matter physics and materials science. A new study now demonstrates how...

Im Focus: New 3-D wiring technique brings scalable quantum computers closer to reality

Researchers from the Institute for Quantum Computing (IQC) at the University of Waterloo led the development of a new extensible wiring technique capable of controlling superconducting quantum bits, representing a significant step towards to the realization of a scalable quantum computer.

"The quantum socket is a wiring method that uses three-dimensional wires based on spring-loaded pins to address individual qubits," said Jeremy Béjanin, a PhD...

Im Focus: Scientists develop a semiconductor nanocomposite material that moves in response to light

In a paper in Scientific Reports, a research team at Worcester Polytechnic Institute describes a novel light-activated phenomenon that could become the basis for applications as diverse as microscopic robotic grippers and more efficient solar cells.

A research team at Worcester Polytechnic Institute (WPI) has developed a revolutionary, light-activated semiconductor nanocomposite material that can be used...

Im Focus: Diamonds aren't forever: Sandia, Harvard team create first quantum computer bridge

By forcefully embedding two silicon atoms in a diamond matrix, Sandia researchers have demonstrated for the first time on a single chip all the components needed to create a quantum bridge to link quantum computers together.

"People have already built small quantum computers," says Sandia researcher Ryan Camacho. "Maybe the first useful one won't be a single giant quantum computer...

All Focus news of the innovation-report >>>



Event News

#IC2S2: When Social Science meets Computer Science - GESIS will host the IC2S2 conference 2017

14.10.2016 | Event News

Agricultural Trade Developments and Potentials in Central Asia and the South Caucasus

14.10.2016 | Event News

World Health Summit – Day Three: A Call to Action

12.10.2016 | Event News

Latest News

3-D-printed magnets

26.10.2016 | Power and Electrical Engineering

Advanced analysis of brain structure shape may track progression to Alzheimer's disease

26.10.2016 | Health and Medicine

3-D-printed structures shrink when heated

26.10.2016 | Materials Sciences

More VideoLinks >>>