Reading aloud The world's smallest hologram was able to pick up Canadian researchers from a single hydrogen atom surrounded by multiple oxygen atoms. This method opens up a new field for the study of new materials or complex biological structures. Their results are presented in the journal Nature (Vol 414, p. 525). Scientists at the Steacie Institute of Molecular Science, Chalk River, Ontario, and Atomic Energy of Canada Ltd. turned to recording. a sample in small steps through a neutron beam. The particularly effective scattering of neutrons at hydrogen atoms within the mineral simpsonite enabled them to image these atoms and the surrounding oxygen layers three-dimensionally. For this high atomic resolution, all neutrons must have the same energy. When analyzing the scattering data, the scientists also had to consider the effects of the crystal environment on the hydrogen atom.
In contrast to established 3D-structure-examinations by X-ray diffraction, with this method no high-purity, exact single crystals need to be elaborately grown. Especially for biological samples, this method of neutron holography is particularly useful because organic material contains many hydrogen atoms, says Ronald Rogge, co-author of the study. In addition, the sample material is significantly more protected in a neutron irradiation than in a structural analysis with X-rays.