Two Washington geophysicists, using diamonds to subject hydrogen to super pressures, have converted the gas into a solid at room temperatures, a historic achievement that may have vast technological implications -- especially for energy production.
The Carnegie Institution scientists said producing hydrogen that is solid at room temperature is a major stride toward the elusive, eagerly sought goal of producing hydrogen that is metallic at room temperature.
Even at ordinary temperatures, it is theorized, metallic hydrogen would be a superconductor, a material offering no resistance to electrical current and, therefore, providing a universe of glittering industrial possibilities.
Although it might be years before it could be put widespread use, a room temperature superconductor would in theory make possible faster computers, more efficient motors and huge strides in generating and transmitting cheap electrical energy.
For a material to be of broad application as a superconductor, it must demonstrate its capacities at ordinary temperatures. Currently available superconductors require extremely low temperatures, disqualifying them from many uses.
According to theory, hydrogen could becomd a metal under a presure of about one million times the pressure produced by the earth's atmosphere, or about 15 million pounds per square inch.
So far, the two Carnegie scientists, Peter M. Bell of Potomac and David Ho-Kwang Mao of Fairfax, have subjected hydrogen at room temperature to about half that much pressure.
The result, solid, but nonmetallic, is a dense, crystallyine substance looking something like salt or sugar.
The crystal was transformed from the original gascous state in apparatus comparable to a tiny vise, which squeezes experimental samples between carefully cut diamond jaws.
Through the vise, known as a diamond anvil cell, the scientists bring to bear forces of about one ton on an arena measuring about 1/100th of an inch across.
Although the forces are relatively modest, the pressure are enormous, since the smaller the surface on which a force acts, the higher the resultant presure.
The initial pressure technology was devised about 20 years ago by geologist Alvin Van Valkenburg. For years, however, according to Mao, pressures greater than 300,000 atmospheres, or about 4 million pounds per square inch, could not be achieved.
Bell and Mao, both geophysicists interested in simulating the titanic pressures within the earth and planets, improved the alignments of the anvil and made other advances.
In January 1978, working at the Carnegie Geophysical Laboratory at 2801 Upton St. NW, the two scientists set a record. They produced pressures of 1.7 million atmospheres, 25.2 million pounds per square inch.
The National Science Foundation, which supported basic research on the use of the diamond anvil described the 1.7 megabar figure as the highest steady pressure ever recorded experimentally.
That was greater than the pressure that in theory would make a metal of hydrogen. Hydrogen however, is not easy to work with. Before reaching the solid state it tends to leak from the chamber.As a solid it is explosive.
Mao and Bell were in the lab on Saturday trying to raise the pressure on solid hydrogen, but an explosion broke the diamond in the anvil, Mao said.
He said the design of the present equipment would be changed. With an improved device, he said, "I think we have a good chance" to reach a million atmospheres of pressure with hydrogen.
Even if hydrogen could be converted into a superconductor at room temperatures, Mao said, it is not known if it would remain a superconductor if the high pressures were relaxed.
"The big question is if it would slip back (to its nonsuperconducting state)" he said in an interview. Before such a problem could be adequately addressed, he added, it would be necessary to obtain hydrogen in the metallic state.
"First," he said, "you have to make it."
The scientists also said that the solid form of high density hydrogen they created would be a valuable fuel for possible nuclear fusion reactors.