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What makes individual snowflake structures so unique? The tiny differences in temperature and pressure during crystal formation yield singular structures for the flakes. But a truly perfect crystalline order is rare for ice, explains Alexandra Brumberg, who is now a PhD candidate at Northwestern University. This photo was taken when she was an undergraduate at Tufts University. “Single-crystal ice requires pure water—something that is difficult to come by naturally, given the presence of various ions and impurities—and slow growth conditions,” she explains. This image, taken at 10× magnification, shows ice with two crystalline domains separated by a river of amorphous ice down the middle. The domains have been etched with a polymer, forming pits that show the two crystals’ different orientations and enabling the researchers to determine which crystalline face was most stable during ice growth. She and her labmates hoped to enable surface studies of water to better understand how various molecules interact with liquid water and ice.
Submitted by Alexandra Brumberg
Read the paper: J. Phys. Chem. B 2014, DOI: 10.1021/acs.jpcb.6b08857
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