Exotic Chemicals from Salt:
Almost everything around you is made of elements that scientists have studied in some detail in the last 200 years. This understanding breaks when elements are subjected to high pressure and temperature . Using an advanced theoretical understanding and extreme conditions , researchers have become the exotic chemical table salt .
Salt is made of one part sodium and one part bleach . If somehow the salt were transported to the center of the Earth , where the pressure is three million times the surface , crystalline structure would change, but the ratio of these two elements would remain the same .
Vitali Prakapenka at the University of Chicago and colleagues wanted to find out what happens if there were an excess of sodium or chlorine at such high pressures. Could you change the relationship between the elements? ” Could ” Prakapenka said, “because the chemical changes completely in those conditions. ” Doing so , the result would not only be the formation of a new compound, but a serious review of what we think about chemistry.
Elemental behavior changes in such high pressures. For example , the oxygen molecules which usually contain two atoms , are decomposed into the increased pressure , and the element forms a box eight atom . Raising the pressure a little about 300,000 atmospheres, and begins to superconduct . Chemists are trying to develop chemicals that exhibit similar properties, but are stable under normal conditions – learn about these exotic compounds can help achieve that goal.
Sodium chloride (ie , table salt ) is a different beast . It is linked in a one -on-one by very strong ionic bonds . However, calculations by Artem Organov Prakapenka colleague at the State University of New York at Stony Brook said that even sodium chloride could be twisted to produce exotic chemicals. These calculations were given precise pressures to which , in presence of an excess of sodium or chlorine , salt may be transformed.
Calculations showed that NaCl3 , Na3Cl , Na2Cl , Na3Cl2 and NaCl7 could all be stable at pressures ranging from 20GPa to 142GPa , where 1GPa is about 10,000 atmospheres of pressure . Physicists high pressure have many models to predict the behavior of the elements in extreme conditions, but rarely the models agree with experiment .
Notably his calculations withstood the test of experiment in at least two cases : Na3Cl and NaCl3 . To run an experiment of this type , a device called luxury diamond anvil cell is needed. The chemicals are added between two diamonds, which can be compressed to produce pressures up to 300GPa . This is what Prakapenka colleague used to Na3Cl and NaCl3 , structures were verified by Prakapenka by X-ray analysis .
” Nobody thought this could happen , given how strong the bond is between sodium and chlorine ,” said Prakapenka . ” What we have shown is that the theory can be translated into the experiment, which is often not the case in the physics of high pressure.”
Malcolm McMahon, professor of physics at high pressure in the University of Edinburgh , said : . “These are amazing results , and are guided by the remarkable theoretical predictions Without tools like that have been built , would not have thought that the sodium chloride could be changed in this way. ”
It may not have any immediate application of the results. Instead , researchers have opened the door for scientists to begin probing other chemicals in the hope of making exotic combinations that can remain stable at room temperature. Diamonds are a good example . In nature , formed in the interior of the Earth when carbon is subjected to extreme pressure. Once formed, they are stable even at ambient conditions. So there may be other similar materials to diamond we can do , there may be others that our current understanding of chemistry has even predicted.
Other implications are not terrestrial . Each planet in our Solar System and Beyond has a vast amount of extreme pressure material. For example , Jupiter is predicted to have metallic hydrogen , hydrogen where electrons are free to move at will. It is hoped that this material becomes a superconductor at room temperature. Understanding how the chemicals we know behave in such conditions would be vital for predicting conditions in the army are discovering exoplanets .
If nothing else, Prakapenka work shows that even something as simple as table salt can be successfully transformed – which means that we still have much to discover about the items we all know.