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A D V A N C E D M A T E R I A L S & P R O C E S S E S | F E B R U A R Y / M A R C H 2 0 1 8 1 1 it paves the way to the elusive goal of 1-nm resolution in x-ray microscopy. www.desy.de/en. Depiction of magnetic moments obtained using the hybrid WL-LSMS modeling technique inside nickel as the temperature rises from left to right. Courtesy of ORNL. MODELING MAGNETISM Researchersat theDOE’sOakRidge National Laboratory (ORNL), Tenn., are using first principles and serious com- report using the 3D coordinates of a real iron-platinum nanoparticle with 6560 iron and 16,627 platinum atoms to find its magnetic properties. Con- trolling magnetism from one direction to another could improve magnetic recording and electric machines, and the work could also lead to develop- ment of strong magnets that are free of rare earth elements. ornl.gov. Two perpendicularly oriented lenses focus an x-ray beam into a small spot. The object under investigation can then be placed into the optical path. Courtesy of DESY, AndrewMorgan/Saša Bajt. puting capability to model magnetic, ferroelectric, and alloy materials at the atomic level. The goal is to deter- mine the temperatures at which these materials lose or gain magnetism or experience a phase transition from a disordered to an ordered state. Well into their allotted 100 million proces- sor hours on ORNL’s Titan supercom- puter, researchers are using a hybrid code that combines Wang-Landau (WL) Monte Carlo and locally self-consistent multiple scattering (LSMS) methods. “We’re combining the efficiency of WL sampling, the speed of the LSMS, and the computing power of Titan to provide a solid first-principles ther- modynamics description of magne- tism,” explains computational scientist Markus Eisenbach. To date, the team has calculated the ground state magnetic proper- ties of an iron-platinum particle and determined the temperature at which a copper-zinc alloy transitions from a disordered to an ordered state. They