POSTMODERN ALCHEMY

Simulations and experiments meet: Machine learning predicts the structures of gold nanoclusters

University of Jyväskylä - Jyväskylän yliopisto

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Atomistic snapshots describing how two thiolate-protected gold nanoclusters of 144 gold atoms each coalesce producing a single larger cluster matching a size that previously has been synthesized. 

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Credit: Maryam Sabooni Asre Hazer, University of Jyväskylä.

Researchers at University of Jyväskylä (Finland) advance understanding of gold nanocluster behavior at elevated temperatures using machine learning-based simulations. This information is crucial in the design of nanomaterials so that their properties can be modified for use in catalysis and other technological applications.

Thiolate protected gold nanoclusters are hybrid nanomaterials with promising applications in nanomedicine, bioimaging and catalysis. However, understanding how these nanoclusters behave under elevated temperatures, which is critical for their use, has remained largely unexplored due to the prohibitive computational cost of traditional simulation methods. 

Record-long simulations of gold nanoclusters

Researchers at the University of Jyväskylä have successfully employed machine learning-driven simulations to investigate the thermal dynamics of Au₁₄₄(SR)₆₀, one of the most well-studied gold nanoclusters. Using a recently developed atomic cluster expansion (ACE) potential trained on extensive density functional theory data, the researchers conducted molecular dynamics simulations extending up to 0.12 microseconds. This is approximately five orders of magnitude longer than what is feasible with conventional quantum chemical methods.

"This work opens new possibilities for understanding how ligand-protected metal nanoclusters behave under realistic operating conditions," says lead author Dr. Maryam Sabooni Asre Hazer. "Through this work, we can observe in atomistic detail how these clusters transform, fragment, and even merge at elevated temperatures over timescales that are relevant for experimental conditions."

Layer-by-layer thermal transformations revealed

The study revealed that thermal effects induce structural changes in a layer-by-layer fashion, starting from the outermost gold-thiolate protective shell. At temperatures between 300 and 550 K, the researchers observed the spontaneous formation of polymer-like chains and ring structures of gold-thiolate units, which can dynamically detach and reattach to the cluster surface. The remaining cluster compositions closely matched those observed in experimental studies, demonstrating the accuracy of the machine learning potential.

"What's particularly exciting is that we can now see how gold atoms migrate between different layers of the cluster and how the surface restructures under thermal stress," explains Dr. Sabooni Asre Hazer. "These processes are directly relevant to understanding why thermally treated gold nanoclusters become effective catalysts."

Gold clusters joined together in the simulation

In an even more remarkable finding, the researchers successfully simulated the complete coalescence of two Au₁₄₄(SR)₆₀ clusters at 550 K. The fusion process produced a larger cluster with composition Au₂₃₉(SR)₆₉, strikingly similar to a gold nanocluster previously synthesized experimentally. 

"The merged cluster exhibited a twinned face-centered cubic metal core structure, matching the symmetry determined from experimental X-ray diffraction data," says Dr. Sabooni Asre Hazer.

Opening new avenues for nanomaterials research

The methodology enables detailed atomistic studies of processes that were previously inaccessible to computational investigation, including cluster-cluster interactions, catalytic activation mechanisms, thermal stability, and inter-particle reactions.

"Our results provide fundamental insights into how ligand-protected nanoclusters behave as they transition toward larger nanoparticles," explains Professor Hannu Häkkinen, who supervised the research. "This knowledge is instrumental for the rational design of nanomaterials with tailored functionalities for catalysis and other applications.", he continues. 

The research was published in Nature Communications. The publication was recognized as an Editors' Highlight in the Inorganic and Physical Chemistry section of Nature Communications.

The work was supported by the Research Council of Finland and the European Research Council (ERC) through the Advanced Grant project DYNANOINT. Computational resources on supercomputers Puhti and Mahti were provided by the Finnish national supercomputing center CSC. 

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Journal

Nature Communications

DOI

10.1038/s41467-025-67700-w 

Method of Research

Imaging analysis

Subject of Research

Not applicable

Article Title

Thermal dynamics and coalescence of Au144(SR)60 clusters from a machine-learned potential

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21st Century Common Sense, Part One

by Ted Glick / February 18th, 2026

A quarter of the way through this century, there is no doubt that the USA and the world are in deep trouble. This is true for everyone, even the families of those most responsible for this state of affairs, the “Epstein class” and those supporting them. Given the fact that the burning of fossils fuels and nukes, the continued reliance on destructive war as a way of determining who runs individual countries, and the growing disparity between the billionaire/multi-multi-millionaire (MMM) class and those who must work for a living, often barely making it—these and related injustices are what must be transcended, must be overcome, asap. The future of the world literally depends upon whether we can transcend them over the coming years.

For us in the United States of America, the immediate issue is the Trumpfascist efforts to impose dictatorial rule to the benefit of the billionaire class and those MMM’s hoping to become billionaires. As of the time of this writing a key next step in the resistance to these efforts is the November, 2026 federal elections, which should result in the Democrats, aligned with progressive Independents like Bernie Sanders, winning control of at least the House of Representatives, as things now appear is very likely.

But even if they take the House and Senate, and even if the percentage of House and Senate members who are strong and consistent progressives grows significantly, this alone will not yield the kind of changes the world desperately needs. For one thing, would-be dictator Trump will still be President, able to use his White House power in destructive ways, like unnecessary and brutal wars, rising economic, racial, gender and other inequality and hateful discrimination, and major attacks on wind, solar and electric vehicles.

A huge problem, up there at the top of the list, is that the history of efforts over the last many centuries to create truly just and democratic societies, run by organized people, not oligarchs, has at best yielded mixed results since the Russian Revolution of 1917.

In a book I wrote and self-published in 2021, five years ago, here is what I put forward as the key aspect of a “winning strategy, the one that is the key link to the social transformation process so urgently needed: the building and deepening of a way of working together and developing organizations that is collaborative, respectful, democratic its core and which, as a result, is truly transformative, built to last.”¹

This has to be our starting point as we try to determine how we change the world. Also necessary is an understanding of the urgency of the climate crisis. More than any other issue, this is one which must always be seen as a top priority. The amount of damage already done and sure to be done in the future, particularly to low-income people, the vast majority of the world’s population, primarily people of color, cannot be underestimated. We are literally running out of time to transition away from fossil fuels and to be about much more community-building and collaborative approaches to solving problems as they escalate as ecosystems, food and water supplies become increasingly less dependable.

Indeed, this existential reality for the entire planet is a reason that change is not just necessary, not just possible, but very much on the agenda of humankind.

As stated by the late Father Paul Mayer, “What history is calling for is nothing less than the creation of a new human being. We must literally reinvent ourselves through the alchemy of the Spirit”—or however one describes that unseen, powerful force in the universe which, down through history, has inspired people to do things which seem impossible—“or perish. We are being divinely summoned to climb another rung on the evolutionary ladder, to another level of human consciousness.”²

To be frank, it is not enough to be against Donald Trump and MAGA, or against the control of both major parties in the USA, the Democrats and the Republicans, or even to be committed to hard work for the next eight and a half months here in the USA to defeat the billionaire-supporting, fascist President Donald Trump. Our problems are too deep to accept this essential next step as the ultimate goal. Short-term, essential goal yes, but looking at things historically, it can only be the first major step in a fundamental, revolutionary process that over time not just saves the planet and its people but, at long last, matches our desires as a species with the way that we organize ourselves, economically, politically, culturally and socially.

ENDNOTES:

• 1
  21st Century Revolution: Through Higher Love, Racial Justice and Democratic Cooperation, p. 22
• 2
  Paul Mayer, Wrestling with Angels” back cover

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Ted Glick has been a progressive activist and organizer since 1968. He is the author of the recently published books, Burglar for Peace and 21st Century Revolution, both available at https://pmpress.org. Read other articles by Ted, or visit Ted's website.

Homunuclus

Church teaching holds that in-vitro fertilization is morally wrong because it replaces the conjugal union between husband and wife and often results in the destruction of embryos. Artificial insemination for married couples is allowable if it "facilitates" the sex act but does not replace it. The church condemns all forms of experimentation on human embryos.Vatican Critical of Stem Cell Creation

The current pope was once Cardinal Ratzinger the Vatican's chief Inquisitor, yes I know we weren't expecting the Spanish Inquistion.

When the issue of cloning and artificial life was presented for JP2, Ratzinger issued the churches statement on bio-ethics which has not changed since the Rennisance when the Church banned sorcery and the creation of artificial life known as the Homunculus And indeed Ratzinger in his paper, refers to cloning as creating a homonucleus. 21st Century science meets the middle ages.

Does the law permit the ìenhancementî or other manipulation of one's genetic outfit? In this context, the following issues were discussed at the seminar: reproduction techniques in general (the "homunculus issue," see Goethe's Faust 11), special issues of "reprogenetics," cloning (inherently wrong, or open to an evaluation between healing effects and human dignity by way of a rule-and- exception relationship?), disease prevention (MV, cancers), unfairly advantaging certain children in view of a "level playing field" of genetic outfits, right of parents to genetically manipulate their offspring, and liability of parents who do not manipulate.The New Genetics and the Law

The crowning example of alchemical hybris came with the claim of pseudo-Paracelsus in the sixteenth century that he could make a homunculus - an artificial man. Like the gold of the alchemists, which was said to exceed the 24 carats of the best natural gold, the homunculus was supposed to be better than a natural man. Being made in a flask from human semen,
he was free of the catamenial substance that, according to the current theories of generation, supplied the material basis to an ordinary fetus. According to pseudo-Paracelsus, the homunculus was a semi-spiritual being that had an immediate apprehension of all the arts and a preternatural intelligence. In modern terms, the homunculus could be called the perfect test-tube baby, engineered to have the highest possible intelligence quota and aptitude. I have written an article focusing on this topic ("The Homunculus and his Forebears," 1999; see Vita), and have a book focusing on alchemy and the art-nature debate under contract (Promethean Ambitions: Alchemy and the Refashioning of Nature, forthcoming with University of Chicago Press). Newton's Alchemy, recreated

What can we make of his account of the creation of a homunculus, a
miniature human being, in his laboratory? Cloning and genetic engineering are clearly impossible with 16th-century technology. Paracelsus

The invention of hand lenses and the microscope facilitated studies of the chick embryo by Marcello Malpighi (1628-1694), but also gave rise to one of the most profound errors in describing human development, that of the homunculus. This was a miniature human believed to have been seen within the head of a human spermatozoon and which presumed to enlarge when deposited in the female. This was the basis of the preformation theory and was believed by many well into the 18th century.lifeissues.net | When Does Human Life Begin? The Final Answer

Drawing of Human Spermatozoa
1694
The drawing was conceived by Niklaas Hartsoeker not by what
he had seen, but what he presumed would be visible if sperm
could be adequately viewed.

Consider the profound difficulty embryonic development presents to an observer. A complex organism, such as a chick, frog, insect or human, arises in an orderly and magical way from an apparently structureless egg. When embryology was in its infancy in the 17th and 18th centuries, the thought was that no animal could arise from such nothingness. Thus was born the theory of the homunculus: the idea that an infinite set of tiny individuals were contained, one within another, in each egg—or in each sperm (there was vigorous disagreement as to which). Development was seen as the visible unfolding of a preexisting individual. Unhappily for this wonderful notion, in the late 18th century Caspar Friedrich Wolff showed by microscopy that embryos contained cells but no homunculus—there was no preformed entity.
American Scientist Online - In the Twinkle of a Fly

U.S. Senator Sam Brownback (R-Kansas) recently told his fellow Republicans he would advance a two-year moratorium rather than a permanent ban. Ironically, Brownback relayed his intentions while President Bush reaffirmed his opposition to human embryo cloning in a speech delivered by satellite to the Southern Baptist Convention in St. Louis. Bush told them, "We believe that a life is a creation, not a commodity, and that our children are gifts to be loved and protected, not products to be designed and manufactured by human cloning." How did we get so quickly from a few cells in a dish to children? It reminds me of artists' representations during the Middle Ages of the homunculus: an invisibly tiny, fully formed human carried around by the male and then deposited in the female during intercourse. The tiny homunculus would eventually grow into a fetus before it was born. Those were the days before the discoveries of the microscope, sperm and egg. So then maybe Bush and Bevilacqua imagine that people still reproduce with homunculi. Otherwise, describing what we know with absolute certainty are nothing more than single or several cells in a microscopic cluster, resembling the cells inside your cheek, as "children" simply doesn't make any sense! If these men didn't wield so much power, we'd laugh at their ignorance. Stem Cells and Cloning: What Bush Doesn't Know Might Kill You ...

Faust and Homunculus
19th century engraving of Goethe's Faust and Homunculus



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21ST CENTURY ALCHEMY

Stanford researchers unveil new material infused with gold in an exotic chemical state

Peer-Reviewed Publication

STANFORD UNIVERSITY

For the first time, Stanford researchers have found a way to create and stabilize an extremely rare form of gold that has lost two negatively charged electrons, denoted Au2+. The material stabilizing this elusive version of the valued element is a halide perovskite—a class of crystalline materials that holds great promise for various applications including more-efficient solar cells, light sources, and electronics components.

Surprisingly, the Au2+ perovskite is also quick and simple to make using off-the-shelf ingredients at room temperature.

"It was a real surprise that we were able to synthesize a stable material containing Au2+—I didn't even believe it at first," said Hemamala Karunadasa, associate professor of chemistry at the Stanford School of Humanities and Sciences and senior author of the study published Aug. 28 in Nature Chemistry. "Creating this first-of-its-kind Au2+ perovskite is exciting. The gold atoms in the perovskite bear strong similarities to the copper atoms in high-temperature superconductors, and heavy atoms with unpaired electrons, like Au2+, show cool magnetic effects not seen in lighter atoms."

"Halide perovskites possess really attractive properties for many everyday applications, so we've been looking to expand this family of materials," said Kurt Lindquist, the lead author of the study who conducted the research as a Stanford doctoral student and is now a postdoctoral scholar in inorganic chemistry at Princeton University. "An unprecedented Au2+ perovskite could open some intriguing new avenues."

Heavy electrons in gold

As an elemental metal, gold has long been valued for its relative scarcity as well as its unmatched malleability and chemical inertness—meaning it can be easily shaped into jewelry and coins that do not react with chemicals in the environment and tarnish over time. An additional key reason for its value is gold's namesake color; arguably no other metal in its pure state has such a distinctively rich hue.

The fundamental physics behind gold's acclaimed appearance also explains why Au2+ is so rare, Karunadasa explained. 

The root reason is relativistic effects, originally postulated in Albert Einstein's famed theory of relativity. "Einstein taught us that when objects move very fast and their velocity approaches a significant fraction of the speed of light, the objects get heavier,” Karunadasa said.

This phenomenon applies to particles, too, and has profound consequences for “massive” heavy elements, such as gold, whose atomic nuclei boast a large number of protons. These particles collectively exert immense positive charge, forcing negatively charged electrons to whirl around the nucleus at breakneck speeds. As a consequence, the electrons grow heavy and tightly surround the nucleus, blunting its charge and allowing outer electrons to drift farther than in typical metals. This rearrangement of electrons and their energy levels leads to gold absorbing blue light and therefore appearing yellow to our eye.

Because of the arrangement of gold's electrons, thanks to relativity, the atom naturally occurs as Au1+ and Au3+, losing one or three electrons, respectively, and spurning Au2+. (The “2+” indicates a net positive charge from the loss of two negatively charged electrons, and the "Au" chemical symbol for gold hails from “aurum,” the Latin word for gold.)

A squeeze of vitamin C

With just the right molecular configuration, Au2+ can endure, the Stanford researchers found. Lindquist said he "stumbled upon" the new Au2+-harboring perovskite while working on a broader project centered on magnetic semiconductors for use in electronic devices.

Lindquist mixed a salt called cesium chloride and Au3+-chloride together in water and added hydrochloric acid to the solution "with a little vitamin C thrown in," he said. In the ensuing reaction, vitamin C (an acid) donates a (negatively charged) electron to the common Au3+ forming Au2+. Intriguingly, Au2+ is stable in the solid perovskite but not in solution.

"In the lab, we can make this material using very simple ingredients in about five minutes at room temperature," said Lindquist. "We end up with a powder that's very dark green, nearly black, and is surprisingly heavy because of the gold it contains."

Recognizing that they may have hit new chemistry paydirt, so to speak, Lindquist performed numerous tests on the perovskite, including spectroscopy and X-ray diffraction, to investigate how it absorbs light and to characterize its crystal structure. Stanford research groups in physics and chemistry led by Young Lee, professor of applied physics and of photon science, and Edward Solomon, the Monroe E. Spaght Professor of Chemistry and professor of photon science, further contributed to studying the behavior of Au2+.

The experiments ultimately bore out the presence of Au2+ in a perovskite and, in the process, added a chapter to a century-old story of chemistry and physics involving Linus Pauling, who received the Nobel Prize in Chemistry in 1954 and the Nobel Peace Prize in 1962. Early in his career, he worked on gold perovskites containing the common forms Au1+ and Au3+. Coincidentally, Pauling also later studied the structure of vitamin C—one of the ingredients required to yield a stable perovskite containing the elusive Au2+.

"We love Linus Pauling’s connection to our work," Karunadasa said. "The synthesis of this perovskite makes for a good story."

Looking ahead, Karunadasa, Lindquist, and colleagues plan to study the new material further and tweak its chemistry. The hope is that an Au2+ perovskite can be used in applications that require magnetism and conductivity as electrons hop from Au2+ to Au3+ in the perovskite.

"We're excited to explore what an Au2+ perovskite could do," Karunadasa said.

Karunadasa is also a senior fellow at the Precourt Institute for Energy and a principal investigator and faculty scientist at the Stanford Institute for Materials and Energy Sciences, SLAC National Accelerator Laboratory. Solomon is a professor of photon science at Stanford Synchrotron Radiation Lightsource, SLAC. Additional Stanford co-authors are Christina R. Deschene and Alexander J. Heyer, graduate students in the Department of Chemistry; and Jiajia Wen, a staff scientist at SLAC. Additional co-authors include Armin Eghdami and Alexander G. Smith, graduate students in the Department of Physics, University of California-Berkeley, and Jeffrey B. Neaton, professor of physics at the University of California-Berkeley; and Dominic H. Ryan, professor of physics at McGill University.

The research was funded in part by the U.S. National Science Foundation, the U.S. Department of Energy, the Fonds de recherche du Québec–Nature et technologies, and the Natural Sciences and Engineering Research Council Canada.

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JOURNAL

Nature Chemistry

DOI

10.1038/s41557-023-01305-y 

ARTICLE TITLE

Stabilizing Au2+ in a mixed-valence 3D halide perovskite

21ST CENTURY ALCHEMY

Techniques honed by Kansas nuclear physicists helped detect creation of gold in Large Hadron Collider collisions

University of Kansas

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ALICE experiment at CERN's Large Hadron Collider, where KU nuclear physicists helped detect gold, briefly, during ultra-peripheral collisions. 

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Credit: CERN

LAWRENCE — Nuclear physicists working at the Large Hadron Collider recently made headlines by achieving the centuries-old dream of alchemists (and nightmare of precious-metals investors): They transformed lead into gold.

At least for a fraction of a second. The scientists reported their results in Physical Reviews.

The accomplishment at the Large Hadron Collider, the 17-mile particle accelerator buried under the French-Swiss border, happened within a sophisticated and sensitive detector called ALICE, a scientific instrument roughly the size of a McMansion.

It was scientists from the University of Kansas, working on the ALICE experiment, who developed the technique that tracked “ultra-peripheral” collisions between protons and ions that made gold in the LHC.

“Usually in collider experiments, we make the particles crash into each other to produce lots of debris,” said Daniel Tapia Takaki, professor of physics and leader of KU’s group at ALICE. “But in ultra-peripheral collisions, we’re interested in what happens when the particles don’t hit each other. These are near misses. The ions pass close enough to interact — but without touching. There’s no physical overlap.”

The ions racing around the LHC tunnel are heavy nuclei with many protons, each generating powerful electric fields. When accelerated, these charged ions emit photons — they shine light.

“When you accelerate an electric charge to near light speeds, it starts shining,” Tapia Takaki said. “One ion can shine light that essentially takes a picture of the other. When that light is energetic enough, it can probe deep inside the other nucleus, like a high-energy flashbulb.”

The KU researcher said during these UPC “flashes” surprising interactions can occur, including the rate event that sparked worldwide attention.

“Sometimes, the photons from both ions interact with each other — what we call photon-photon collisions,” he said. “These events are incredibly clean, with almost nothing else produced. They contrast with typical collisions where we see sprays of particles flying everywhere.”

However, the ALICE detector and the LHC were designed to collect data on head-on collisions that result in messy sprays of particles.

“These clean interactions were hard to detect with earlier setups,” Tapia Takaki said. “Our group at KU pioneered new techniques to study them. We built up this expertise years ago when it was not a popular subject.”

These methods allowed for the news-making discovery that the LHC team transmuted lead into gold momentarily via ultra-peripheral collisions where lead ions lose three protons (turning the speck of lead into a gold speck) for a fraction of a second.

Tapia Takaki’s KU co-authors on the paper are graduate student Anna Binoy; graduate student Amrit Gautam; postdoctoral researcher Tommaso Isidori; postdoctoral research assistant Anisa Khatun; and research scientist Nicola Minafra.

The KU team at the LHC ALICE experiment plans to continue studying the ultra-peripheral collisions. Tapia Takaki said that while the creation of gold fascinated the public, the potential of understanding the interactions goes deeper.

“This light is so energetic, it can knock protons out of the nucleus,” he said. “Sometimes one, sometimes two, three or even four protons. We can see these ejected protons directly with our detectors.”

Each proton removed changes the elements: One gives thallium, two gives mercury, three gives gold.

“These new nuclei are very short-lived,” he said. “They decay quickly, but not always immediately. Sometimes they travel along the beamline and hit parts of the collider — triggering safety systems.”

That’s why this research matters beyond the headlines.

“With proposals for future colliders even larger than the LHC — some up to 100 kilometers in Europe and China — you need to understand these nuclear byproducts,” Tapia Takaki said. “This ‘alchemy’ may be crucial for designing the next generation of machines.”

This work was supported by the U.S. Department of Energy Office of Science, Office of Nuclear Physics.

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DOI

10.1103/PhysRevC.111.054906