Chemistry news and discussions

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Metallic bond between two beryllium atoms made for the first time
https://phys.org/news/2023-06-metallic- ... atoms.html
by Bob Yirka , Phys.org

A quartet of chemists at the University of Oxford has, for the first time, found a way to get two beryllium atoms to bond with one another. In their paper published in the journal Science, Josef Boronski, Agamemnon Crumpton, Lewis Wales and Simon Aldridge, describe their process and how they managed to do it in a safe way—and at room temperature. Jason Dutton with La Trobe University, has published a Perspective piece in the same journal issue, outlining the work done by the team in England.

Beryllium is a strong but lightweight, alkaline earth metal. It is also brittle.

Beryllium only ever occurs naturally when mixed with other elements, forming minerals. It is often found in gemstones such as emeralds. And it is used in a variety of applications, from telecommunications equipment to computers and cell phones. It is also mixed with other metals to create alloys used in applications such as gyroscopes and electrical contacts.

For many years, scientists have thought that the element could be even more useful if a way could be found to force beryllium atoms to bond with one another. But until now, it was not possible.

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Scientists develop a new class of artificial water channels for more efficient industrial water purification
https://phys.org/news/2023-08-scientist ... cient.html
by National University of Singapore

A team led by scientists from the National University of Singapore's (NUS) Department of Biological Sciences in collaboration with the French Center for Scientific Research (CNRS) has successfully synthesized a special protein-mimic that can self-assemble into a pore structure. When incorporated into a lipid membrane, the pores permit selective transport of water across the membrane while rejecting salt (ions).

These protein-mimics, known as 'oligourea foldamers,' represent an entirely new class of artificial water channels (AWC) that can be used to improve the energy-efficiency of current methods of industrial water purification.

Current methods of water purification involve the use of reverse osmosis and membrane distillation technologies. Reverse osmosis, however, is a highly energy-intensive process as high pressures are needed to pass seawater or wastewater through a series of semi-permeable membranes to remove salts and other pollutants.

[weatheriscool]

New, simple and accessible method creates potency-increasing structure in drugs
https://phys.org/news/2023-08-simple-ac ... drugs.html
by Pennsylvania State University

Chemical structures called cyclopropanes can increase the potency and fine-tune the properties of many drugs, but traditional methods to create this structure only work with certain molecules and require highly reactive—potentially explosive—ingredients.

Now, a team of researchers from Penn State has identified and demonstrated a safe, efficient and practical way to create cyclopropanes on a wide variety of molecules using a previously undescribed chemical process. With additional development, the new method—described in a paper publishing Aug. 4 in the journal Science—could transform how this important process occurs during drug development and creation.

[weatheriscool]

Pivotal discovery in sensor technology eliminates faulty electronic sensors when measuring toxins in water
https://phys.org/news/2023-08-pivotal-d ... aulty.html
by Joseph E. Harmon, Argonne National Laboratory

There is a global water crisis, and it is not only about the dwindling supply of clean water. Contaminated drinking water exposes hundreds of millions of people worldwide to toxins, such as bacteria, heavy metals, pesticides and coronaviruses. This contamination imperils public health and can cause serious illnesses.

A team of researchers from the U.S. Department of Energy's Argonne National Laboratory, along with the Pritzker School of Molecular Engineering at the University of Chicago and the University of Wisconsin—Milwaukee, has devised a pathway for the mass manufacture of sensors able to simultaneously detect lead, mercury and E. coli. in flowing tap water. The team's innovation promises to help safeguard public health by providing early warning for contamination.

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Scientists theorize a hidden phase transition between liquid and a solid
https://phys.org/news/2023-08-scientist ... ition.html
by Rachel Berkowitz, Lawrence Berkeley National Laboratory

Anything made out of plastic or glass is known as an amorphous material. Unlike many materials that freeze into crystalline solids, the atoms and molecules in amorphous materials never stack together to form crystals when cooled. In fact, although we commonly think of plastic and glass as "solids," they instead remain in a state that is more accurately described as a supercooled liquid that flows extremely slowly.

And although these "glassy dynamic" materials are ubiquitous in our daily lives, how they become rigid at the microscopic scale has long eluded scientists.

Now, researchers at the Department of Energy's Lawrence Berkeley National Laboratory (Berkeley Lab) have discovered molecular behavior in supercooled liquids that represents a hidden phase transition between a liquid and a solid.

Their improved understanding applies to ordinary materials like plastics and glass, and could help scientists develop new amorphous materials for use in medical devices, drug delivery, and additive manufacturing.

Specifically, using theory, computer simulations, and previous experiments, the scientists explained why the molecules in these materials, when cooled, remain disordered like a liquid until taking a sharp turn toward a solid-like state at a certain temperature called the onset temperature—effectively becoming so viscous that they barely move. This onset of rigidity—a previously unknown phase transition—is what separates supercooled from normal liquids.

[firestar464]

Not sure if this is the right place to post this, but they made a super-strong eco-friendly glass.

https://www.bbc.com/news/business-66359047

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A new way to identify chiral molecules with light could vastly improve detection efficiency
https://phys.org/news/2023-08-chiral-mo ... iency.html
by Imperial College London

Chiral molecules are those that have two versions that are mirror images, like our right and left hands. These molecules have the same structure but different properties when they interact with other molecules, including those inside our bodies. This is important for example in drug molecules, where only the right- or left-handed version may have the desired effect.

Detecting and quantifying the chirality of matter however has been difficult. Current methods using a form of light that produces a (right- or left-twisting) helix have the problem that each turn of the helix is much larger than the molecules. This creates important challenges for

[weatheriscool]

Machine learning tool simplifies one of the most widely used reactions in the pharmaceutical industry
https://phys.org/news/2023-09-machine-t ... tical.html
by Tracy Crane, University of Illinois at Urbana-Champaign

In the past two decades, the carbon-nitrogen bond forming reaction, known as the Buchwald-Hartwig reaction, has become one of the most widely used tools in organic synthesis, particularly in the pharmaceutical industry given the prevalence of nitrogen in natural products and pharmaceuticals.

This powerful reaction has revolutionized the way nitrogen-containing compounds are made in academic and industrial laboratories, but it requires lengthy, time-consuming experimentation to determine the best conditions for a highly effective reaction.

Now, Illinois researchers in collaboration with chemists at Hoffman La-Roche, a pharmaceutical company in Switzerland, have developed a machine learning tool that predicts in a matter of minutes the best conditions for a high-yielding reaction with no lengthy experimentation.

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Reducing the carbon footprint of methane by converting it into methanol with a new enzyme
https://phys.org/news/2023-09-carbon-fo ... nzyme.html
by Nagoya University

A team led by Professor Osami Shoji at Nagoya University in Japan has developed a technology to convert methane, the principal component of natural gas, into methanol at room temperature in water. They used an enzyme that can be easily mass-produced, offering the possibility of a cheap and effective means to reduce the carbon footprint of natural gas. They published the results in ACS Catalysis.

Methane is the key component of natural gas and an abundant natural resource. However, it is chemically stable, requiring huge amounts of energy before it undergoes chemical conversion. One solution is to convert methane to methanol.

Methane can be converted to methanol, which is cleaner than other fossil fuels and can be easily stored and transported. Converting methane to methanol can be done using the methane monooxygenase enzyme. However, the enzyme has a complex structure, making it difficult to handle and unsuitable for mass production.

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Scientists finally detected O-28. It's instability surprised them
https://www.sciencenews.org/article/oxy ... se-physics

Using a powerful particle accelerator, researchers have spotted an elusive variant of oxygen for the first time. The isotope, oxygen-28, was predicted to be stable thanks to its eight protons and 20 neutrons — “magic” numbers associated with extra stability in atomic nuclei.

Atomic nuclei are made up of protons and neutrons, each of which are thought to occupy their own “shells” — discrete energy levels that are separated by large energy gaps. Atomic nuclei with full outer shells are bound extra tightly, making them very stable. Shells fill up when they hit two, eight, 20, 28, 50, 82 and 126 subatomic particles (SN: 10/9/13).

Finding the isotope took a combination of brute force and experimental elegance. Physicist Yosuke Kondo of the Tokyo Institute of Technology and colleagues used a particle accelerator to smash calcium-48 atoms against a beryllium target. This fragmented the calcium-48 atoms into lighter isotopes, including fluorine-29. Throwing the fluorine-29 against a liquid hydrogen target knocked off a single proton, producing oxygen-28.”

Scientists expected the isotope to be stable, but it isn’t: it sloughs off 4 neutrons in a femtosecond (1E-21 sec). O-28’s surprising instability indicates there’s something we don’t understand about the strong nuclear force, which binds together protons and neutrons in the atomic nucleus.

[wjfox]

Tiny ‘quantum dot’ particles win chemistry Nobel

04 October 2023

Three chemists who predicted and were first to make quantum dots — nanoscale crystals that interact with light in unusual ways — have been awarded the Nobel Prize in Chemistry.

Moungi Bawendi at the Massachusetts Institute of Technology in Cambridge, Louis Brus at Columbia University in New York City and Alexei Ekimov at New York City-based company Nanocrystals Technology will each receive one-third of the 11-million-Swedish-krona (US$1-million) prize.

“It’s an amazing result for the quantum-dot community,” says Mark Green, a physicist at King’s College London. “The theoretical frameworks provided by Brus and Ekimov were made into a reality with Bawendi’s seminal paper in 1993, from which this now-mature science sprung.”

Quantum dots are semiconductor crystals consisting of just a few thousand atoms, which have some properties of single atoms. This allows them to be tuned so they can emit specific wavelengths of light. Very small quantum dots of cadmium selenide, for example, can emit blue light, but bigger crystals of the same compound emit red light. Quantum dots are used in applications that need specific wavelengths of light, from bright television displays to biological imaging.

https://www.nature.com/articles/d41586-023-03048-9

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Water can evaporate with just light, no heat, says surprising study
By Michael Irving
October 31, 2023

Contrary to what we all learned in elementary school science class, it turns out that heat may not be necessary to make water evaporate. Scientists at MIT have made the surprising discovery that light alone can evaporate water, and is even more efficient at it than heat. The finding could improve our understanding of natural phenomena or boost desalination systems.

Evaporation occurs when water molecules near the surface of the liquid absorb enough energy to escape into the air above as a gas – water vapor. Generally, heat is the energy source, and in the case of Earth’s water cycle, that heat comes primarily from sunlight.

https://newatlas.com/science/water-evap ... t-no-heat/

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Chemists make breakthrough in drug discovery chemistry: Two methods to replace carbon with a nitrogen atom in a molecule
https://phys.org/news/2023-11-chemists- ... istry.html
by Louise Lerner, University of Chicago

For years, if you asked the people working to create new pharmaceutical drugs what they wished for, at the top of their lists would be a way to easily replace a carbon atom with a nitrogen atom in a molecule.

But two studies from chemists at the University of Chicago, published in Science and Nature, offer two new methods to address this wish. The findings could make it easier to develop new drugs.

"This is the grand-challenge problem that I started my lab to try to solve," said Mark Levin, an associate professor of chemistry and the senior author on both papers. "We haven't totally solved it, but we've taken two really big bites out of the problem, and these findings lay a clear foundation for the future."

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Deep learning model can detect a previously unknown quasicrystalline phase
https://phys.org/news/2023-11-deep-prev ... phase.html
by Tokyo University of Science

Crystalline materials are made up of atoms, ions, or molecules arranged in an ordered, three-dimensional structure. They are widely used for the development of semiconductors, pharmaceuticals, photovoltaics, and catalysts.

The type of structures that fall into the category of crystalline materials continues to expand as scientists design novel materials to address emerging challenges pertaining to energy storage, carbon capture, and advanced electronics.

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New AI model identifies new pharmaceutical ingredients and improves existing ones
https://phys.org/news/2023-11-ai-pharma ... ients.html
by Daniel Meierhans, ETH Zurich

New active pharmaceutical ingredients lay the foundations for innovative and better medical treatments. However, identifying them and, above all, producing them through chemical synthesis in the laboratory is no mean feat. To home in on the optimum production process, chemists normally use a trial-and-error approach: they derive possible methods for laboratory synthesis from known chemical reactions and then test each one with experiments, a time-consuming approach that is littered with dead ends.

Now, scientists at ETH Zurich, together with researchers from Roche Pharma Research and Early Development, have come up with an approach based on artificial intelligence that helps to determine the best synthesis method, including its probability of success. Their paper is published in the journal Nature Chemistry.

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Researchers develop biodegradable polymers that are traceable without toxic contrast agents
https://phys.org/news/2023-11-biodegrad ... trast.html
by J. G. M. Van Den Elshout, University of Twente

Polyphosphoesters, molecules containing phosphorus as the central element, are easily traceable without the need for contrast agents, thanks to developments by researchers from the University of Twente (UT). Normally, these molecules display a similar molecular composition to our DNA, leading to considerable "noise" in the image.

The UT researchers provided a solution and developed unique polymers that are traceable with magnetic resonance imaging (MRI). Dr. Olga Koshkina, Project Leader in the Sustainable Polymer Chemistry Group, published this new concept of traceable polymers in Communications Chemistry.

The researchers adjusted the properties of polyphosphoesters (special polymers with a molecular structure inspired by DNA and RNA). As a result, the polymers acquired a different "MRI color," making them more distinguishable from the natural background. Additionally, they exhibit other physical MRI characteristics suitable for imaging.

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]Neutron scattering study points the way to electrochemical for carbon-neutral ammonia
https://phys.org/news/2023-12-neutron-e ... monia.html
by Sumner Brown Gibbs, Oak Ridge National Laboratory

Scientists from Stanford University and the Department of Energy's Oak Ridge National Laboratory are turning air into fertilizer without leaving a carbon footprint. Their discovery could deliver a much-needed solution to help meet worldwide carbon-neutral goals by 2050.

Published in the journal Energy & Environmental Science, the study describes a sustainable electrochemical—rather than chemical—process for producing ammonia, a key ingredient for nitrogen fertilizer.

In essence, the researchers used neutron scattering to understand how cycling an electric current during the conversion of nitrogen to ammonia, also known as the nitrogen reduction reaction, increases the amount of ammonia produced. This process has the potential to enable farmers to convert nitrogen, the most abundant element in our atmosphere, into ammonia-based fertilizers without emit

ting carbon dioxide.

[Tadasuke]

I've always considered chemistry (and basically all science, even if I studied it) as awful. I literally hate, hate, hate how all of it works. It doesn't seem appealing or fun in the slightest, no matter how many years pass and the more I know, the more I hate it.

However, my view is, that we unfortunately really need to study all of it, in order to learn how to create virtual realities, where everything works totally differently, how we like, not how we are forced. But first we have to understand, learn and teach, how this awful universe works. Then, we may be able to make a fundamentally different one, and perhaps even erase our memories from this one (at least for some time).

On the one hand I understood pupils at school who didn't want to learn, but at the same time I explained that we need to learn in order to escape this f***ed up reality by building a different one. Of course I was usually laughed at, but whatever. Not everyone fits to a group well. Chemistry is certainly important and essential.

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A 3D magnesiophilic substrate enables planar electroplating/stripping of magnesium metal anode

by Zhang Nannan, Chinese Academy of Sciences

As a promising candidate to current lithium-ion batteries, rechargeable magnesium batteries have attracted extensive attention due to the superior properties of magnesium (Mg) metal anodes, such as high volumetric capacity (3,833 mAh/cm3), abundant resources, environmental friendliness, and difficult to grow dendrites.

Although some studies have reported that the morphology of Mg dendrites can be observed under extreme electroplating conditions, such as using the limited Mg electrolytes with low Mg-ion conductivity and applying ultra-high current density (10 mAh/cm2), these test conditions are clearly different from practical requirements.

Researchers from the Qingdao Institute of Bioenergy and Bioprocess Technology of the Chinese Academy of Sciences (CAS) have discovered that the use of the practical polyolefin separator indeed causes the short-circuit of coin cell even at the low current density. They have established a layer-by-layer planar growth model for short-circuit suppression, and proposed the design strategy of a 3D magnesiophilic substrate to achieve planar Mg electroplating/stripping behavior.

The study was published in ACS Energy Letters on Dec. 4.

Ample evidence has shown that Mg growth is uniform and dense when the current density is below 5 mAh/cm2. However, using practical polyolefin separators with the thin thickness, low-current charging and discharging can cause internal short-circuiting in coin cells.

The researchers have proposed the island-growth model for Mg deposits based on electrochemical tests and microscopic morphology observation, which reasonably explains the abnormal short-circuit behavior.

https://phys.org/news/2023-12-3d-magnes ... lanar.html

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New catalytic technique creates key component of incontinence drug in less time
https://phys.org/news/2024-01-catalytic ... nence.html
by Nagoya University

A research group at Nagoya University in Japan has developed a new catalyst that promises to revolutionize the asymmetric synthesis of pharmaceuticals called chiral macrocyclic dilithium(I) salt. It overcomes the lack of reactivity of ketones and the difficulty inducing them to arrange atoms, which are common challenges in drug-making.

The researchers used their technique to synthesize a key intermediate of the incontinence drug oxybutynin. Their catalyst promises to contribute to future drug discovery and development. They published their results in the Journal of the American Chemical Society.