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#The material with the MIDAS touch: New supercooled liquid instantly glows gold when it's touched By Jonathan O'Callaghan for Mailonline Published: 09:15 GMT, 15 may 2015 Updated: 09:22 GMT, 15 may 2015 A material has been demonstrated that crystallises and produces light as soon as it is touched. Called an organic supercooled liquid, a video captures the moment the material becomes extremely bright after being rubbed by a crystal. And the results may be useful in creating better memory storage systems for computers or medical sensors. Scroll down for video University of Michigan scientists have demonstrated a supercool liquid. The liquid is below its freezing point but is not a solid until touched. When rubbed by another crystal it suddenly begins to crystallise (shown. Credit: American Chemical Societythe research, reported by the American Chemical Society, was carried out by Kyeongwoon Chung and Dr Jinsang Kim from the University of Michigan. The researchers studied a chemical called DPP (diketopyrrolopyrrole), which has been used widely in dyes and organic electronics applications. The organic molecules of this chemical are used widely in electronic devices such as solar cells, LEDS and transistors. By tinkering with the ide chainsof the molecules-essentially, the parts that keep them attached together-they found they could alter how they behaved below their freezing point. This meant they were able to make the molecules remain liquid when cooled below their melting temperature of 134°C (273°F). Typically this would also be the material's freezing point. Instead, the molecules stay in a stable, upercooledliquid state down to 5°C (41°F), at which point the molecules solidify into a Glass in addition to the unusually broad temperature range for the supercooled liquid state, the group found that it crystallised when rubbed with a stylus, changing from dark red to bright yellow when put under a UV light. The rubbing broke the balance in the side chains of the molecules, allowing them to link up and produce the effect.''The glowing phenomenon is so-called photo luminescence. High energy photons are absorbed to the molecule and pump ground state electrons to the excited states, 'Dr Kim told Mailonline.''When the excited electrons come back to the ground state the excess energy appears as light emission and the colour is determined by the band gap of the molecule.''Under ambient light you cannot see the emission normally.''At high temperatures around 100°C (212°F) when the molecules moved freely, just a touch could make the entire film or droplet crystallise. t's like a domino effect, Dr Kim said in a statement. But at room temperature, the thicker supercooled liquid crystallised only where the stylus made contact, allowing the first author on the paper, Kyeongwoon Chung, a U-M doctoral student, to scrawl messages such as hear-triggered crystal. he researchers said the molecule may be useful in biosensors, which could reveal the characteristics of cells for medical diagnosis. The ability to write and erase luminescent information also suggests the potential for use in computer memory that encodes information with light rather than magnetism g

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