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The shape of snow: New insights could help climate models

2023/07/172023/08/31

Scientists from the Institut des Géosciences de l’Environnement of Grenoble, the Centre d’Etudes de la Neige and the Groupe de Météorologie Expérimentale et Instrumentale have developed a new approach for measuring the interaction between snow and sunlight. This methodology is important to improve the accuracy of climate models. They did X-ray tomography experiments at ESRF ID19 beamline. The results are published in Nature Communications.

Once deposited on the ground, snow is a material composed of air and ice crystals, whose shape and arrangement vary greatly at the micrometre scale. This is known as the microstructure of snow. This “skeleton” of ice and air governs the propagation of light within the snowpack through optical phenomena such as refraction and internal reflections in the ice phase.

However, despite its extreme complexity and irregularity, natural snow is still represented in a simplistic manner in almost all optical models, including those implemented in climate models. These models typically depict snow as a collection of ice particles with perfect geometric shapes, mainly spheres. Among the many implications for the energy balance of snow, this simplification leads to significant uncertainties in climate modelling, with potential impacts of up to 1.2°C on global air temperature.

In this new study, the authors from the Institut des Géosciences de l’Environnement of Grenoble (IGE / CNRS – INRAE – IRD – UGA – Grenoble INP-UGA), the Centre d’Etudes de la Neige (CEN / CNRM / Météo-France – CNRS) and the Groupe de Météorologie Expérimentale et Instrumentale (GMEI / CNRM / Météo-France – CNRS) have accurately simulated the light propagation in a collection of 3D images of snow microstructure obtained by X-ray tomography, using a ray-tracing model. Very different snow types were investigated, from fresh snow (PP) to refrozen melt-freeze forms (MF). Some images were obtained at the 3SR-Lab. Several snow microstructures required higher resolution and were acquired at ESRF beamline ID19.

Image: Snow microstructure: This is what fresh snow looks like at the micrometre scale

The key to why plants flower early in a warming world

2023/07/032023/07/12

Scientists have unveiled a new mechanism that plants use to sense temperature. This finding could lead to solutions to counteract some of the deleterious changes in plant growth, flowering and seed production due to climate change. The results are published today in PNAS.

The rise of temperatures worldwide due to climate change is having detrimental consequences for plants. They tend to flower earlier than before and rush through the reproductive process, which translates into less fruits and less seeds and reduced biomass.

Scientists are now working on the plants’ circadian clock, which determines their growth, metabolism and when they flower. The key thermosensor of the circadian clock is EARLY FLOWERING 3 (ELF3), a protein that plays a vital role in plant development. It integrates various environmental cues, such as light and temperature, with internal developmental signals, to regulate the expression of flowering genes and determine when plants grow and bloom.

A team from the ESRF, CEA and CNRS have determined the molecular mechanism of how ELF3 works in vitro and in the model plant Arabidopsis thaliana. As temperature rises, ELF3 undergoes a process called phase separation. This means that two liquid phases co-exist, in a similar way to oil and water. “We believe that when it goes through phase separation, it sequesters different protein partners like transcription factors, which translates into faster growth and early flowering as a function of elevated temperature”, explains Chloe Zubieta, CNRS Research Director from the Laboratoire de Physiologie Cellulaire et Vegetale at the CEA Grenoble (CNRS/Univ. Grenoble Alpes/CEA/INRAE UMR 5168) and co-corresponding author of the publication. “We are trying to understand the biophysics of the prion-like domain inside ELF3, which we think is the responsible for this phase separation.

ELF3 is a flexible protein, with no well-defined structure, so it cannot be studied using X-ray crystallography, as it needs to be in solution. Instead, the team used mainly Small Angle X-ray Scattering. All existing models showed that the structure would be highly disordered. Then the surprise came up: “I’ve seen many prion-like domains involved in phase separation, but this is the first time I saw something fundamentally different”, explains Mark Tully, ESRF scientist on BM29 and co-corresponding author of the publication.

New hope in the fight against malaria

2023/06/132023/06/14

Scientists have identified and characterized a new inhibitor that prevents the malaria parasite to infect human red blood cells. It is non-toxic to human cells and targets a nanomotor of the parasite. Structural studies conducted at the ESRF beamlines, in collaboration with teams from the Curie Institute and Vermont University, elucidate the novel mode of inhibition that paves the way for new preventative medications against this disease. The results are published today in Nature Communications.

Malaria infection in humans, caused by the Plasmodium parasites and transmitted via the bite of an infected Anopheles mosquito, is a prominent global health issue. In 2020, malaria caused 627,000 deaths, the majority being children under the age of five according to the WHO. In 2021, nearly half of the world’s population was at risk of malaria. The European Centre for Disease Prevention and Control states that with global climate change, there is a risk that malaria appears in Europe in the coming decades.

In recent years, there has been a remarkable progress in antimalarial therapeutics. However, the parasite is developing resistance to all existing treatments, including current first-line treatments containing artemisinin-based therapies. The first ever malaria vaccine is on the market since October 2021, however its efficacy is relatively modest.

Therefore, the international community is still on the lookout for novel treatments. Six years ago, an international collaboration of scientists, including the Institut Curie in France (Julien Robert-Paganin & Anne Houdusse), the University of Vermont in the USA (Kathleen Trybus) and Imperial College in the United Kingdom (Jake Baum) investigated a large molecular complex called the glideosome that plays a crucial role in the movement of the Plasmodium falciparum (Pf) parasite.

Image: Dihia Moussaoui, co-first author of the paper and post-doctoral researcher at the ESRF, during the experiments at the structural beamline ID30B at the ESRF, the European Synchrotron

Credit: ESRF

X-ray nanotomography reveals 3D microstructure of graphite anodes for lithium-ion batteries

2023/05/172023/05/25

The optimisation of battery electrode architecture is a key aspect of improving battery performance, provided that precise characterisation of the complex battery microstructure is possible. In this work, X-ray nanotomography [1] was used at beamline ID16B [2] to obtain high-resolution images of the microstructure of graphite battery electrodes, providing 3D analysis and thorough quantification of the electrode/particle inner structure and porosity at the nanoscale.

A crucial step in the production of battery-grade natural graphite for lithium-ion batteries is the spheroidisation process: the morphological change that occurs in the electrode material during cycling or charging/discharging cycles. However, the low yield (30-50%) of this process results in a large quantity of wasted graphite fines that are not suitable for use in lithium-ion batteries due to their small particle size [3]. A method was devised to recycle waste graphite fines via a re-agglomeration process followed by a petroleum pitch coating in order to obtain aggregated graphite particles with sound mechanical strength and battery-suitable size to be used for electrode preparation. A compression step called ‘calendering’ was applied to the electrode’s coating to reduce its thickness and consequently increase its volumetric capacity.

X-ray nanotomography measurements carried out at beamline ID16B provided important microstructural details of the electrode-representative volumes (128 × 128 × 108 µm³ with 50 nm voxel size), along with statistical analysis of ~500 particles imaged in a single measurement. Data acquired on non-calendered and calendered pristine electrodes show that higher electrode density could be reached by calendering the electrode, without considerably affecting the active material accessibility through diffusion in the pore network. Despite the considerable morphological changes, no clear agglomerate fractures were observed, and particle integrity was preserved as individual agglomerate particles could still be distinguished. This highlights the fact that structural integrity is maintained from the electrode scale down to the particle level, and that the calendering process does not compromise the electrochemical performance.

Image: lectrode and particle porosity evolution with calendering in terms of (a) pore volume fraction and (b-e) microstructure. 3D rendering views of the (b) non-calendered and (c) calendered electrodes and (d,e) corresponding isolated graphite aggregated particles (with cross-section images).

Cement hydration in 4D: towards a reduction in emissions

2023/05/102023/05/11

Researchers led by the University of Málaga show the Portland cement early age hydration with microscopic detail and high contrast between the components. This knowledge may contribute to more environmentally friendly cements. The results are now published in Nature Communications.

Concrete is a fluid mass that strikingly sets and hardens in hours, even under water. This fabricated rock, which is made of cement, water, sand and gravel, is the basic building block of our civilization. Hence, it is not a surprise that it is the world’s largest manufactured commodity. The enormous production of Portland cement (PC), at 4 billion tonnes per year, results in 2.7 billion tonnes of CO2 emissions per year. If cement production were considered a country, it would be the third CO2 emitter in the world, just after China and USA. Therefore, reducing the CO2 footprint of cement, mortar and concrete is a societal need.

The main drawback of the current proposals for low-carbon cements is the slow hydration kinetics in the first 3 days. “Understanding the processes related to cement hydration as it takes place at its early stages is crucial”, explains Shiva Shirani, first author of the paper and PhD student at the University of Malaga. Despite a century of research, our understanding of cement dissolution and precipitation processes at early ages is very limited. “So we have developed a methodology to get a full picture of the hydration of Portland cement”, she adds.

The team, which is led by the University of Málaga and includes the ESRF, the Paul Scherrer Institute PSI (Switzerland) and the University Grenoble Alpes (France), carried out a tomographic study in the laboratory for an initial characterisation, followed by phase-contrast microtomography experiments with synchrotron radiation to take data very quickly and in large sample volumes, and finally experiments at the nanometric scale, using synchrotron ptychotomography.

Image: Scientists followed the hydration process of cement in its early stages

Credit: Shiva Shirani

$X-ray diffraction reveals ancient Egyptian illustration methods$

X-ray diffraction reveals ancient Egyptian illustration methods

2023/03/232023/03/30

The ancient Egyptians used papyrus as a medium for communication and illustration, with the first illustrations appearing in the fifth and sixth dynasties (2500 – 2100 B.C.). Funerary documents, such as the Book of the Dead, flourished during the New Kingdom period as they were considered essential for entering the afterlife.

The Champollion Museum in Vif, France, holds a collection of 280 papyrus fragments, many of which show scenes from the Book of the Dead. The colours used in these illustrations are typical of the Egyptian palette and include blue, green, red, pink, yellow and white, with different characters and elements of the illustrations outlined with a black line.

Researchers from the ESRF and the Néel Institute CNRS/UGA in Grenoble, France, with collaborators from the Champollion Museum, worked together to gain a deeper understanding of the illustration processs used in ancient Egypt. A combination of optical microscopy, synchrotron X-ray powder diffraction, X-ray fluorescence and Raman spectroscopy was used to identify the pigments and their overall distribution.

Two of the papyrus fragments of the collection (PAP-6 and PAP-12) were examined on beamline ID22, where X-ray fluorescence and X-ray diffraction experiments were carried out. Mixed Rietveld and Pawley refinement was carried out against the XRD data to quantify the fine fraction and to consider the heterogeneous microstructure of the pigments.

Environmental pollutants found incrusted in iron in endometriotic lesions

2023/03/142023/03/14

Scientists led by Istituto Di Ricovero e Cura a Carattere Scientifico (IRCCS), the Italian Research Hospital Burlo Garofolo in Trieste show that iron presence in endometriosis is associated to the accumulation of environmental metals, supporting the idea that the environment exposure to toxic chemicals plays a role in the disease.

Around 1 in 10 women in reproductive age around the world live with endometriosis, an inflammatory disease caused when tissue similar to the lining of the uterus grows outside the womb, such as in the ovaries and fallopian tubes. This causes pain and, in many cases, infertility. Even if women have always been affected by endometriosis, it is only since recently that the scientific community has started looking into it.

The factors that may lead to endometriosis go from genetic predisposition to autoimmune diseases and environmental triggers. Now a team from Institute for Maternal and Child health IRCCS Burlo Garofolo in Trieste (Italy) has found the presence of iron clustered with environmental metals, such as lead, aluminium or titanium, using beamlines ID21 and id16B at the ESRF.

The accumulation of iron in endometriosis was already well documented. Iron deposits are common in endometrial lesions, indicating an altered iron metabolism. “We knew that iron can create oxidative stress and hence, inflammation, as it does in other conditions, such as asbestosis, so we wanted to know more about what chemical form it takes, how it is distributed and whether there are other environmental pollutants with it”, explains Lorella Pascolo, leader of the study.

Pascolo and her team came to the ESRF to compare iron nanoaggregates in endometrial lesions of patients with normal endometrium samples of the same patients. “The ESRF beamlines are exceptional instruments to get a clear picture of the role of iron and how it transforms into endometrial lesions”, explains Pascolo.

They used X-ray fluorescence (XRF) on beamline ID21 to track the presence and distribution of iron and environmental pollutants, and ID16B to fine-tune the findings and reveal additional heavy metals at the nano level. They also used X-ray spectroscopy to reveal the chemical state of the iron.

Unusual compound found in Rembrandt’s The Night Watch

2023/01/172023/01/18

An international team of scientists from the Rijksmuseum, the CNRS, the ESRF the European Synchrotron, the University of Amsterdam and the University of Antwerp, have discovered a rare lead compound (named lead formate) in Rembrandt’s masterpiece The Night Watch. This discovery, which is a first in the history of the scientific study of paintings, provides new insight into 17th-century painting technique and the conservation history of the masterpiece. The study is published in Angewandte Chemie – International edition.

The Night Watch, painted in 1642 and displayed today in the Rijksmuseum Amsterdam (The Netherlands), is one of Rembrandt’s most important masterpieces and largest work of art. In the framework of the 2019 Operation Night Watch, the largest research and conservation project ever undertaken for Rembrandt’s masterpiece, an international research team joined forces to study how the painting materials react chemically and with time.

The team of scientists combined multi-scale imaging methods in order to chemically study the materials used by Rembrandt in The Night Watch. A X-ray scanning instrument developed at the University of Antwerp (Belgium) was applied directly to the painting, while tiny fragments taken from the painting were studied with synchrotron micro X-ray probes, at the ESRF, the European Synchrotron (France), and PETRA-III facility (Germany). These two types of analyses revealed the presence of an unexpected organo-metallic compound: lead formates. This compound had never been detected before in historic paintings: “In paintings, lead formates have only been reported once in 2020, but in model paintings (mock-up, fresh paints). And there lies the surprise: not only do we discover lead formates, but we identify them in areas where there is no lead pigment, white, yellow. We think that probably they disappear fast, this is why they were not detected in old master paintings until now”, explains Victor Gonzalez, CNRS researcher at the Supramolecular and Macromolecular Photophysics and Photochemistry (PPSM) laboratory (CNRS/ENS Paris-Saclay) and first author of the paper.

Image: The Night Watch, Rembrandt van Rijn, 1642

Credit: Rijskmuseum Amsterdam

Scientists find the presence of fluids derived from subducted slab in the lower mantle

2022/12/162023/01/12

A team of scientists, led by University College Cork (Ireland) and Bayreuth Geoinstitute (Germany), has found proof of subducted slab fluids in the lower mantle by studying inclusions in diamonds using the ESRF.

In the Juína region, in the west of Brazil, a volcanic eruption brought diamonds from the interior of the Earth to the surface around 93 millions of years ago. Diamonds form perfect capsules so they retain the exact chemistry of material from the part of the Earth where they formed. Scientists are therefore studying these minerals to get information on the composition of the deep upper mantle, the transition zone and lower mantle.

Now a team led by University College Cork (Ireland) and Bayreuth Geoinstitute (Germany) has found that subducted material has penetrated into the sublithosperic mantle (below 250 km) by testing the oxidation state of several diamonds from the Juína region using the ESRF.

The oxidation state of the Earth’s mantle controls important parameters and processes, such as magma generation, speciation and mobility of fluids and melts in the Earth’s interior, deep carbon cycle, recycling of oceanic crust back into the mantle, chemical differentiation of the planet and many others.

It is generally considered that the main three layers of the Earth – its crust, mantle and core, represent profound changes in the oxidation state of iron from ferric (Fe3+) at the surface to mostly Fe2+ in the silicate minerals in the upper mantle, transition zone and the lower mantle and ultimately, to the Fe0 in the core. In short, the surface is very oxidised and the core is metallic so it is very reduced.

Image: Georgios Aprilis, ESRF postdoc at ID18 beamline

Andrea Ilari & Adriana Erica Miele’s #My1stLight Memories

2022/12/052022/12/06

Long COVID and pulmonary fibrosis better understood thanks to innovative techniques

2022/11/012022/11/03

An international team of researchers has revealed how scarring occurs in Long-COVID and pulmonary fibrosis using innovative blood biomarkers and X-ray technology. This study, published in The Lancet – eBioMedicine, contributes to the knowledge on the pathophysiology of severe COVID-19 and thus its treatment.

Long-COVID syndrome, or the origin of the long-term consequences of SARS-CoV-2 infection, is still not fully understood, more than two years after the onset of the pandemic. In particular, the long-term changes in lung tissue following severe COVID-19 disease pose significant limitations for many patients. Some of these patients continue to develop post-COVID pulmonary fibrosis, which is characterised by rapid scarring of the lung tissue.

Until now, the scientific community didn’t understand the underlying mechanisms of this scarring and of specific blood markers that can predict this process. Now, an international research team led by doctors and researchers at the Institute of Pathology at the RWTH Aachen University Hospital, the Hannover Medical School (MHH), HELIOS University Hospital in Wuppertal, and the University Medical Center Mainz, in collaboration with scientists at University College London (UCL) and the European Synchrotron (ESRF), has uncovered the mechanism that modifies the connective tissue of the lung in severe COVID-19. By combining the latest in imaging and molecular biology techniques this multidisciplinary team uncovered a mechanism by which the connective tissue of the lung is modified in severe COVID-19. They have demonstrated how COVID-19 changes the structure of the finest blood vessels in the lung and found molecular markers of this damage in the blood of patients that might ultimately help diagnose and treat the condition.

The history of one of the oldest objects in the Solar system unveiled

2022/09/232022/10/12

An international team of scientists have unveiled details of the history of the asteroid Ryugu, a truly ancient object in the Solar system, after the Hayabusa2 mission brought samples from this asteroid back to Earth. The ESRF was one of the institutes involved in sample characterization, on ID15A. The results are published in Science.

The asteroid Ryugu, located at 200 million kilometres from the Earth, is one of the most primitive objects of the solar system. The Japanese spacecraft Hayabusa2 explored it from 2018 until it came back to Earth two years later with minuscule multiple samples from the asteroid.

Two years later, and thanks to the international collaboration of institutes led by the Japan Aerospace Exploration Agency (JAXA), the first results on the analysis of the samples shed light on the history of Ryugu, from its formation to its collisional destruction.

Researchers used cosmochemical and physical methods at universities and institutes, including the ESRF and four other synchrotron radiation facilities in Japan, United States, and Europe.

The results combined with computer simulation have allowed scientists to picture the origins of Ryugu: the Ryugu parent body accumulated about 2 million years after the formation of the solar system, and then heated up to about 50°C over the next 3 million years, resulting in chemical reactions between water and rock. The size of the impactor that destroyed the Ryugu parent body, which is about 100 km in diameter, is at most 10 km in diameter, and that the present-day Ryugu is composed of material from a region far from the impact point.

What the data explain

In particular, the seventeen Ryugu samples analysed contain particles (such as Ca- and Al-rich inclusions) that were formed in high-temperature environments (>1000°C). These high-temperature particles are thought to have formed near the Sun and then migrated to the outer solar system, where Ryugu was formed. This indicates that large-scale mixing of materials occurred between the inner and outer solar system at the time of its birth.

Based on the detection of the magnetic field left in the Ryugu samples, it is highly likely that the original asteroid from which the current Ryugu descended (Ryugu’s parent body) was born in the darkness of nebular gas, far from the Sun, where sunlight cannot reach.

The scientists also discovered liquid water trapped in a crystal in a sample. This water was carbonated water containing salts and organic matter, which was once present in the Ryugu parent body. Crystals shaped as coral reefs grew from the liquid water that existed inside Ryugu’s parent body. Rocks that were deeper underground contained more water than those in the surface.

Image: A coloured view of the C-type asteroid 162173 Ryugu, seen by the ONC-T camera on board of Hayabusa2.

Credit: JAXA Hayabusa 2

New insight into how mammal ancestors became warm-blooded

2022/07/202022/08/11

The shapes of the ear canals of mammal ancestors reveal when warm-bloodedness evolved. The study published in Nature demonstrates that mammal ancestors became warm-blooded later than previously thought – nearly 20 million years later-, and that the acquisition of endothermy seems to have occurred very quickly in geological terms, in less than a million years. The international team of scientists, led by London’s Natural History Museum, the University of Lisbon’s Instituto Superior Técnico, the Field Museum in Chicago, and including the University of Witwatersrand, used the ESRF bright X-rays to scan delicate and dense fossils.

Image: Comparison of bony labyrinth shape in two examples of warm-blooded (left) and cold-blooded (right) prehistoric mammal ancestors. © Romain David and Ricardo Araújo.

Antibody rigidity regulates immune activity

2022/07/132022/07/15

Scientists at the University of Southampton have gained unprecedented new insight into the key properties of an antibody needed to stimulate immune activity to fight off cancer, using the ESRF’s structural biology beamlines, among others.

The interdisciplinary study, published in Science Immunology, revealed how changing the flexibility of the antibody could stimulate a stronger immune response. The findings have enabled the team to design antibodies to activate important receptors on immune cells to “fire them up” and deliver more powerful anti-cancer effects. The researchers believe their findings could pave the way to improve antibody drugs that target cancer, as well as automimmune diseases.

In the study, the team investigated antibody drugs targeting the receptor CD40 for cancer treatment. Clinical development has been hampered by a lack of understanding of how to stimulate the receptors to the right level. The problem being that if antibodies are too active they can become toxic. Previous research by the same team had shown that a specific type of antibody called IgG2 is uniquely suited as a template for pharmaceutical intervention, since it is more active than other antibody types. However, the reason why it is more active had not been determined. What was known, however, is that the structure between the antibody arms, the so called hinges, changes over time.

This latest research harnesses this property of the hinge and explains how it works: the researchers call this process “disulfide-switching”. In their study, the team analysed the effect of modifying the hinge and used a combination of biological activity assays, structural biology, and computational chemistry to study how disulfide switching alters antibody structure and activity.

Image: Flexibility of the monoclonal antibody F(ab) arms is conferred by the hinge region disulphide structure

Credit: C. Orr

It sucked to be the prey of ancient cephalopods

2022/06/232022/06/30

The Jurassic cephalopod Vampyronassa rhodanica, thought to be the oldest known ancestor of the modern-day vampire squid (Vampyroteuthis infernalis), was likely an active hunter – a mode of life that is in contrast with its opportunistic descendant. Scientists led by Sorbonne University came to this conclusion after analysing microtomographic data of this rare fossil, acquired at the ESRF and the Muséum national d’Histoire naturelle in Paris. The results are published today in Scientific Reports.

Vampyronassa rhodanica is thought to be one of the oldest relatives of the modern-day vampire squid (Vampyroteuthis infernalis), which is the only remaining living species of its family. This modern form lives in extreme deep ocean environments, often with little oxygen, and feeds on drifting organic matter. Like V. infernalis, the body of V. rhodanica was mostly made of soft tissue. As this rarely fossilises, little is known about the physical characteristics and evolutionary history of this family.

Despite the scarcity of fossil material from this family, Alison Rowe, from Sorbonne University and colleagues were able to study 3 well-preserved V. rhodanica specimens from La Voulte-sur-Rhône (Ardèche, France), dating to more than 164 million years ago. The eight-armed specimens were small, measuring around 10 cm in length, and had elongated oval-shaped bodies with two small fins.

They took them to the ESRF for non-destructive 3-D imaging: “We used synchrotron tomography at the ESRF in order to better identify the outlines of the various anatomical features”, says Rowe. However, the task was challenging, as Vincent Fernández, scientist at the ESRF, explains: “The fossils are on small slabs, which are very difficult to scan. On top of that, soft tissues are preserved but we needed phase contrast imaging to visualise the faint density variation in the data. The coherence of beamline ID19 was therefore very important to perform propagation phase-contrast computed-tomography and track all the minute details, such as the suckers and small fleshy extensions, called cirri”.

Image: Hypothesised reconstruction of Vampyronassa rhodanica

Credit: A. Lethiers, CR2P-SU

Scientists synthesise new materials at terapascal pressures for the first time

2022/05/122022/05/12

A team led by the University of Bayreuth (Germany) has synthesized, for the first time, new materials at terapascal pressures, using the ESRF’s ID11 and a unique diamond anvil cell. The results are published in the journal Nature.

Matter changes with variations of pressure and temperature, which allows the tuning of many material properties. These possibilities can shed light onto scientific questions, such as the fundamental understanding of the Universe or lead to targeted design of advanced materials. For example, today super-abrasive cubic Boron Nitride is used for grinding high-quality tool steels and artificial diamonds created using high temperature and high pressure are more prevalent than natural ones.

A team of scientists led by the University of Bayreuth has synthesized new materials at terapascal pressures using laser heating for the first time. The team used rhenium-nitrogen compounds as models to show that studies at pressures three times higher than pressure in the center of the Earth are now possible. Natalia Dubrovinskaya, professor at the University of Bayreuth and one of the corresponding authors of the paper, explains the relevance of these compounds: “These novel rhenium-nitrogen compounds showed that at ultra-high pressures we can make materials that cannot be made at lower pressures/temperatures, and uncover fundamental rules of physics and chemistry. We found, for example, that due to a huge compression, rhenium behaves chemically in a similar way to iron”.

Image: Schematic illustration of the Diamond Anvil Cell assembly

Credit: Timofey Fedotenko