Question: 5 fold diffraction pattern symmetries were discovered in 1982 by dan shechtman when he discovered this phase which opened new field of study in quasiperiodic crystals

 On April 8, 1982, while on sabbatical at the U.S. National Bureau of Standards in Washington, D.C., Shechtman discovered the icosahedral phase, which opened the new field of quasiperiodic crystals. Dan Shechtman (Hebrew: דן שכטמן; born January 24, 1941) is the Philip Tobias Professor of Materials Science at the Technion – Israel Institute of Technology, an Associate of the US Department of Energy's Ames Laboratory, and Professor of Materials Science at Iowa State University.  Shechtman was awarded the 2011 Nobel Prize in Chemistry for the discovery of quasicrystals, making him one of six Israelis who have won the Nobel Prize in Chemistry. <SEP> Alan Lindsay Mackay FRS (born 6 September 1926) is a British crystallographer, born in Wolverhampton.  He spent his scientific career at Birkbeck College, founded by George Birkbeck, one of the Colleges of the University of London, where he was immersed in a liberal scientific atmosphere under the leadership of John Desmond Bernal.  He became a Fellow of the Royal Society (FRS) on 17 March 1988 and a Fellow of Birkbeck College on 2 March 2002.  He is also a Fellow of the Mexican Academy of Sciences.  Mackay has made important scientific contributions related to the structure of materials: In 1962 he published a manuscript that showed how to pack atoms in an icosahedral fashion; a first step towards five-fold symmetry in materials science.  These arrangements are now called Mackay icosahedra.  He is a pioneer in the introduction of five-fold symmetry in materials and in 1981 predicted quasicrystals in a paper (in Russian) entitled "De Nive Quinquangula" in which he used a Penrose tiling in two and three dimensions to predict a new kind of ordered structures not allowed by traditional crystallography.  In a later manuscript, in 1982, he took the optical Fourier transform of a 2-D Penrose tiling decorated with atoms, obtaining a pattern with sharp spots and five-fold symmetry.  This brought the possibility of identifying quasiperiodic order in a material through diffraction.  Quasicrystals with icosahedral symmetry were found by Dan Shechtman and co-workers in 1984.  For his contributions to quasicrystals in 2010 Mackay was awarded the Buckley Prize, <SEP> George-ericksenite is a mineral with the chemical formula NaCaMg(IO)(CrO)(HO).  It is vitreous, pale yellow to bright lemon yellow, brittle, and features a prismatic to acicular crystal habit along [001] and somewhat flattened crystal habit on {110}.  It was first encountered in 1984 at the Pinch Mineralogical Museum.  One specimen of dietzeite from Oficina Chacabuco, Chile had bright lemon-yellow micronodules on it.  These crystals produced an X-ray powder diffraction pattern that did not match any XRD data listed for inorganic compounds.  The X-ray diffraction pattern and powder mount were set aside until 1994.  By then, the entire mineral collection from the Pinch Mineralogical Museum had been purchased by the Canadian Museum of Nature.  The specimen was then retrieved and studied further.  This study was successful and the new mineral george-ericksenite was discovered.  The mineral was named for George E. Ericksen who was a research economic geologist with the U.S. Geological Survey for fifty years.  The mineral and name have been approved by Commission on New Minerals and Mineral Names (IMA).  The specimen, polished thin section, and the actual crystal used for the structure determination are kept in the Display Series of the National Mineral Collection of Canada at the Canadian Museum of Nature, Ottawa, Ontario. <SEP>  However, quasicrystals can occur with other diffraction pattern symmetries, such as 5-fold; these were not discovered until 1982 by Dan Shechtman. The crystallographic restriction theorem in its basic form was based on the observation that the rotational symmetries of a crystal are usually limited to 2-fold, 3-fold, 4-fold, and 6-fold.