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Experimenting with a magnetic field almost 1M times stronger than that of the Earth, researchers in the Scholes Group were able to modify the optoelectronic properties of model nonmagnetic organic chromophores. The modifications, according to the paper, arise from the induction of ring currents in the aromatic molecules. Aromatic ring currents can be understood as the proposal that electrons delocalized by aromaticity will move circularly when a magnetic field is applied perpendicular to the aromatic plane, typically nudging chemical shifts of nearby atoms in NMR spectroscopy. For the experiment, researchers chose a model aromatic chromophore called a phthalocyanine, which has...

For most of human history, the distant ‘celestial sphere’ was regarded as perfect and unchanging. Stars remained in place, planets moved predictably, and the few rogue comets were viewed as atmospheric phenomena. This began to change with the Danish astronomer Tycho Brahe’s observation of the supernova of 1572 – apparently, a new star – and his studies of the Great Comet of 1577, which he proved was actually a distant object. Nonetheless, the impression of permanence is strong. There are very few astronomical objects that noticeably vary to the naked eye: only the brightest comets, novae and supernovae. For observers...

Raman spectroscopy souped up with scanning tunnelling microscopy hones in on individual atoms and bonds. Prepare to take flight across the surface of a molecule. An unprecedented window on the nanoscale world lets you feel the heft of the atoms beneath and test the strength of the chemical bonds that hold them together. This vision is now a reality, thanks to a system reported in this week's Nature1 that combines the best features of two imaging techniques: Raman spectroscopy and the scanning tunnelling microscope (STM). “It enables you to look at the guts of a molecule,” says Joanna Atkin, a...

The analysis revealed the image of an upturned face underneath the fresco © Bianca Jackson and Dominique Martos-LevifA collaboration between analytical scientists and the Louvre in France has revealed a hidden work under one of the museum’s frescoes. The research is an example of the broadening field of terahertz spectroscopy, using wavelengths of electromagnetic radiation between microwave and infrared.The fresco, Trois hommes armes de lances, is part of the Louvre’s Campana collection – pieces that once belonged to Giampietro Campana, an excavator and collector of ancient artifacts in the 19th century. Campana was known to restore the pieces he obtained...

Single-molecule spectroscopy can provide new insights into the dynamics of biological and material science, but analysing the data from this technique is no simple task. To this end, scientists in Germany have developed a new method for tracking single fluorescent molecules, using linear programming solvers.Whereas previous methods have involved tracking by hand or with semi-manual systems, this new algorithm means standard computers can be used instead, freeing up the researchersÂ’ time and reducing the risk of mistakes. This new technique is essential for the on-going miniaturization of devices to the nanoscale.Single-molecule spectroscopy can be used to observe the translational and...

Spectroscopy, a key method of identifying atoms and molecules with light, has been taken to its most fundamental level - a single photon absorbed by a single molecule. In addition to paving the way toward new experiments that observe the interaction between light and matter at its most basic level, the researchers that accomplished the feat suggest that their technique could also work with other photon-emitters, including those under study for quantum communication.Spectroscopy works by finding the frequencies of light that will put an atom or molecule into an excited state - these comprise the chemical's unique absorption and emission...

Spontaneous refolding of amyloid fibres under mild conditions could provide insight into Alzheimer's disease claim scientists in the US. Amyloids are collections of twisted or misfolded proteins and often develop in the brains of people with a number of neurodegenerative diseases, including Alzheimer's and Parkinson's. They have been considered to be the most thermodynamically stable form of protein as very harsh conditions are required to disrupt them. But Igor Lednev and his team at the University of Albany have found amyloid fibres change from one polymorph to another with just mild changes in solution temperature and salinity. Lednev hopes this discovery will provide insight...

NASA claims definitive detection of Moon water in the Solar System's 'attic'.On the way to a wet landing.N. GRUMMAN, W. FURLONG/NASA The debate is finally over. Lunar scientists have detected water for certain near the north pole of the Moon, after the impact of a NASA projectile kicked up water vapour along with a plume of dust. But it's not just about the water, say the scientists, who found hints in the plume of other, more exotic molecules, ranging from organic hydrocarbons to mercury. Increasingly, the scientists are viewing the polar craters as the 'attics' of the Solar System, repositories...

The Star Trek vision of analysing rocks and minerals with the sweep of a handheld device has taken a step towards becoming science rather than science fiction. "We are developing a tricorder," said Robert Downs, associate professor of geosciences at The University of Arizona in Tucson. Professor Downs is using a technique called Raman spectroscopy to compile a library of spectral fingerprints for all the Earth's minerals. About 1,500 of the 4,000 known minerals have been catalogued so far. Although the current Raman spectrometer takes up an area the size of a tabletop, Professor Downs's colleague M. Bonner Denton, a...

CHAMPAIGN, Ill. -- A powerful new tool for probing molecular structure on surfaces has been developed by researchers at the University of Illinois at Urbana-Champaign. Single molecule absorption spectroscopy can enhance molecular analysis, surface manipulation and studies of molecular energy and reactivity at the atomic level. "This new measurement method combines the chemical selectivity of optical absorption spectroscopy with the atomic-scale resolution of scanning tunneling microscopy," said Martin Gruebele, a professor of chemistry, physics and biophysics and corresponding author of a paper accepted for publication in the journal Nano Letters, and posted on its Web site. "The method literally feels...