under normal conditions, hydrogen is the lightest of the gases, but for almost 80 years, physicists have suspected that this root has also the figure of metal. The famous Russian physicist Vitaly Ginzburg during his Nobel lecture in December 2003, metallic hydrogen is put in the list the biggest challenges and dreams of physics of the new century.
Barely 13 years after this prediction, physicists from Cambridge, in the United States, reported in the latest journal “Science”, they managed to produce metallic hydrogen!
Rank R. Diaz, and Isaac F. Silvera of Harvard University write that under the pressure of 495 gigapaskali and at a temperature of 5.5 Kelvin (i.e., 5.5 degrees above absolute zero) molecular hydrogen is turned into metal.
díaz and silver still not convinced that it is a metal in the solid or liquid state, but, in their opinion, everything points to which is hydrogen solidified, crystalline.
Can nadprzewodnikiem at room temperature and contribute to the solution of energy problems of mankind, and revolutionize the rocket drive – according to U.S. researchers.
Hydrogen at the head of the metals?
Hydrogen in the periodic table is located on top of the first group, which contains the same alkali metals, and lithium, sodium, potassium, rubidium, cesium and France. It is not surprising that scientists have long thought that if he also has his metal form.
Under normal pressure in a gaseous state, as well as liquid and solid (hydrogen condenseries at a temperature of 20 ° C and solidifies at a temperature of 14), this element does not conduct current because the hydrogen atoms combine into molecular pairs and share their single electrons. Not enough so that free electrons, which in metals form a series of conductivity and are carriers.
Only the strong compression of the hydrogen to the binding between atoms have been destroyed, gives hope that the electrons will be ejected, and the hydrogen goes into the metal. In 1935, Eugene Wigner and Hillard bell Huntington estimated that this will take place under a pressure of 25 gigapaskali and 250 thousand times more than the atmospheric pressure.
Since then, the achievement of metallic hydrogen was the Holy Grail of high pressure physics
Expedition after the hydrogen Holy Grail
In many laboratories tried to do it several times even proclaimed a success, after which it was canceled. Getting gigantic pressures is not easy, especially because the rating Wignera and Huntington’s was understated, and physicists quickly discovered that in order to learn metallic character of hydrogen, it needs to strain to pressure several million times greater than at the Earth’s surface. Similar to or even higher than what prevails in the center of the planet.
Most of the work in “Science” devoted to a description of how it was possible to achieve in the laboratory the extreme conditions.
Physics the arms of the hydrogen kowadełkach of diamonds, which is the hardest known natural materials. But despite this, when the pressure exceeded one hundred gigapaskali, diamond burst and kruszał like porcelain. The reason was, probably, protects that occurs when grinding kowadełek and penetration of hydrogen into the lattice structure of the diamond.
Both of these problems have found a solution, however – przypowierzchniowa layer diamond kowadełek was “suppressed” and is covered with an aluminium layer covers a shallow, impermeable to hydrogen atoms.
Metallic hydrogen as a diamond
If hydrogen only metal remained under immense pressure in a specially designed kowadełkach probably would still be interesting and of great practical value. Although from a cognitive point of view, of course, is an exciting discovery. Astrophysics can, for example, to better understand what is happening in the bowels of the enormous planets Jupiter and Saturn, where the hydrogen is in such extreme conditions.
But physics from Harvard, hoping for more. I expect that metallic hydrogen is a phase of metastabilną, and will remain a metal after reducing the pressure to normal value
in the Same way as, for example, diamonds that are produced under huge pressures in the depths of the Earth, and after removing to the surface, retain their crystalline form, although other varieties of coal, for example, graphite – have a structure more favorable energetically.
what is metastabilność? Imagine Syzyfa which rolls the stone up the mountain due to the huge power and energy. Once weakened and let go of the prop, the stone is rolled back, but if the slope was a little hole, the stone can get stuck, like an egg in foremce. So usadowiony himself will not participate (you need to provide him with energy, i.e., to push out of the holes). Metastabilne United such energy “cavity”, which provide communications chemical stability and durability, despite the fact that should to collapse, ie to enter into a state of low energy.
If a metal and hydrogen is super easy and really was metastabilny, even today it is hard to imagine all of its applications. It would be a dream material for many applications.
so What do we do with this?
In 1968. Neil Ashcroft, a physicist from Cornell University, predicted that a metallic phase of hydrogen can be nadprzewodząca, i.e. will conduct current without any thermal losses and it is roughly at a temperature above 0 degrees Celsius. It will save a third of the electricity that today we are losing in transmission, and as a result of heating of any electronic device.
Ashcroft also wrote about other applications of this metal – superlekkich structures with which to build entire cities floating in the ocean. And the fuel that was four times more calories than liquid hydrogen used today in the most powerful space rockets.
it Sounds like a fairy tale, and a bit like the story of the miraculous invention of the “Doll” of Boleslaw Prus, where Professor Geist cheats Stanislaus Wokulskiego promise of creating a metal lighter than air.
This story, however, has a chance of becoming reality.
Read: a natural History of hydrogen, that is how this element contributed to the development of our civilization.
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