Scientists Discover A New Form Of Ice β It's Square
J Thoendell stashed this in Science
Geim said that a couple of years ago, they did some theoretical work that suggested they might see square, room temperature ice, though he didn't think they actually would.
"To our own surprise, we found exactly what theory predicted: an ice which is only one atom thick," Geim says.
Ice, of course, is just a crystal. And a crystal is just a material with an orderly arrangement of atoms or molecules. Almost all the ice on Earth is so-called hexagonal ice β that's why snowflakes have six-fold symmetry.
But when water is compressed, like under a massive ice sheet, other crystal structures can form, says Alan Soper, a physicist and expert on the structure of water at Rutherford Appleton Laboratory in the U.K. village of Harwell.
Almost all known forms of ice, including our familiar hexagonal ice, are made up of an underlying motif of water molecules arranged into triangular pyramids, or tetrahedrons, Soper says. But this new form of ice, described in the journal Nature, doesn't have that.
"What's really odd about it is, it loses this tetrahedral structure," Soper says. "That is the thing that's quite surprising, because I don't think it's been observed before."