On the way to the perfect glass

May 27, 2005
On the way to the perfect glass

Researchers from the United Kingdom, France and the DUBBLE beamline at the European Synchrotron Radiation Facility (ESRF) have made a step forward in research on glass. They have monitored the change in the structure of zeolites, crystalline solids, into an almost perfect glass when heated. They have done this by recording vibrations involving groups of atoms in zeolites that subsequently characterise the glass. Their results are published today in Science.

Image: Computer simulations of zeolites (left) and what could be the perfect glass (right). Credits: Florian Meneau

Zeolites are porous crystalline aluminosilicates, presenting a regular arrangement of cages. In their natural state, they are components of soils and can be barriers against the migration of radioactive elements. In their synthetic form, zeolites are industrially applied as components of washing powders and in the cracking of petroleum to make gasoline.

Due to their cage structure, zeolites have a low-density structure. They melt at around 900°C, lower temperatures than most similar materials, such as silica (sand), which melts at twice this temperature. If the heating is carried out at a slow rate, low-frequency vibrational modes are responsible for destabilizing the microporous crystalline structure. When the cages collapse, zeolites contract, becoming 60% more denseheavier than in their original form, and they adopt the structure of a glass. “We have discovered the triggering mechanism”, says Neville Greaves, first author of the paper.

The result is a mechanically and chemically stronger glass than the glass used nowadays. “We believe this is the key to the synthesis of perfect glasses”, asserts Neville Greaves. Would this mean no more broken wine glasses? “This research could lead to that, but it is still far away. This would also mean making glass invulnerable to water, for instance”, he explains. The final aim is to find out the conditions in which the perfect glass forms.

Scientists from the University of Wales, Aberystwyth, the DUBBLE beamline at the ESRF, the Ecole Nationale Supérieure de Chimie of Paris (ENSCP) and ISIS have characterized the low-frequency vibrations that appear in zeolites during heating. The team has carried out their research in neutron as well as X-ray facilities. ISIS is a neutron and muon source located in the UK and a large part of the research presented was done there. The researchers also used a unique X-ray diffraction technique on the Dutch-Belgian beamline (DUBBLE) at the ESRF to determine the degree of crystallinity from zeolites to glass, critical to evaluate the neutron scattering results. “It is really great to combine synchrotron and neutron techniques in the same observation”, explains Greaves.

Source: European Synchrotron Radiation Facility (ESRF)

Related Stories

Recommended for you

Roboticists learn to teach robots from babies

December 1, 2015

Babies learn about the world by exploring how their bodies move in space, grabbing toys, pushing things off tables and by watching and imitating what adults are doing.

A quantum of light for materials science

December 1, 2015

Computer simulations that predict the light-induced change in the physical and chemical properties of complex systems, molecules, nanostructures and solids usually ignore the quantum nature of light. Scientists of the Max-Planck ...

Exiled exoplanet likely kicked out of star's neighborhood

December 1, 2015

A planet discovered last year sitting at an unusually large distance from its star - 16 times farther than Pluto is from the sun - may have been kicked out of its birthplace close to the star in a process similar to what ...


Please sign in to add a comment. Registration is free, and takes less than a minute. Read more

Click here to reset your password.
Sign in to get notified via email when new comments are made.