Dense hydrogen in a new light

Jun 03, 2013
Dense hydrogen in a new light

(Phys.org) —Hydrogen is the most abundant element in the universe. The way it responds under extreme pressures and temperatures is crucial to our understanding of matter and the nature of hydrogen-rich planets.

New work from Carnegie scientists using intense infrared radiation shines new light on this fundamental material at and reveals the details of a surprising new form of solid hydrogen.

Under normal conditions hydrogen is a gas consisting of diatomic molecules. The start to change as the pressure increases. These different forms are called phases and hydrogen has three known solid ones. It has been speculated that at high pressures hydrogen even transforms to a metal, which means it conducts electricity. It could even become a superconductor or a superfluid that never freezes–a completely new and exotic state of matter.

In a new paper published in Physical Review Letters, a team from Carnegie's Geophysical Laboratory examined the structure, bonding and of highly compressed hydrogen using intense .

Using a facility maintained by the Geophysical Laboratory at the at Brookhaven National Laboratory, the team found the new form to be stable from about 2.2 million times normal atmospheric pressure and about 80 degrees Fahrenheit to at least 3.4 million times atmospheric pressure and about -100 degrees Fahrenheit.

Their experiments revealed that hydrogen takes a form under these conditions that differs remarkably from its other known structures. The new phase has two very different types of hydrogen molecules in its structure. One type of molecule interacts very weakly with its neighboring molecules—unusual for molecules under this type of very high compression. The other type of molecule bonds with its neighbors, forming surprising planar sheets.

The measurements also show that solid hydrogen under these conditions is on the borderline between a semiconductor, like silicon, and a semimetal, like graphite. The results disprove earlier claims that hydrogen forms a dense atomic metal at these pressures and temperatures.

"This simple element–with only one electron and one proton–continues to surprise us with its richness and complexity when it is subjected to high pressures," Russell Hemley, Director of the Geophysical Laboratory, said. "The results provide an important testing ground for fundamental theory."

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vacuum-mechanics
1 / 5 (7) Jun 04, 2013
"This simple element–with only one electron and one proton–continues to surprise us with its richness and complexity when it is subjected to high pressures," Russell Hemley, Director of the Geophysical Laboratory, said. "The results provide an important testing ground for fundamental theory."

By the way, even the simple - one electron and one proton of hydrogen atom model still has a problem. According to the classical – Bohr shell model, the electron which circulates about the proton nucleus was criticized that it would radiate energy and spirals into the nucleus. While a better model according to quantum mechanics in which the electron has the probability location around the proton nucleus, still cannot explain why it can stay separate from the proton nucleus, could we solve it?
http://www.vacuum...19〈=en
antialias_physorg
4 / 5 (4) Jun 04, 2013
quantum mechanics...still cannot explain why it can stay separate from the proton nucleus

Yes it can. When you confine an electron to a tighter space you have to allow for increase in momentum (uncertainty principle).
Such a strong confinement that the electron would get on top of the proton (creating a neutron) would take more average momentum than the electrostatic attraction between electron and proton can muster.
So the electron stays at an 'optimum distance'.
(which is sort of a bad picture because to really get this you have to solve the schroedinger equation and you get the image of a standing wave - with the probability of the electron actually being in/very near the nucleus astronomicaly close to zero).
Ober
3 / 5 (2) Jun 05, 2013
I wonder if we just said "Yes, you are right Vacuum". Do you think he would go away??
No, I think not, so it doesn't really matter how we answer him. He won't listen to your informative post antialias, which is a shame.

@Vacuum, the electron doesn't fall into the nucleus because GOD made it that way!!!!

Answer 2

Think of it this way Vacuum. YOU are attracted to a women. As you approach a woman, they soon realise what a creep you are, and run for it. Hence there is no chance of you colliding with a woman.

It's simple really. No need for perturbation theory and probabilities etc, just make up shite, and go with the flow. As for YOU Vacuum, you're probably best to stick with masturbation theory.