Alexander Rakhlin named director of the MIT Statistics and Data Science Center

Alexander “Sasha” Rakhlin PhD ’06, the Distinguished Professor in Data, Systems, and Society at the MIT Institute for Data, Systems, and Society (IDSS); and a professor of brain and cognitive sciences at MIT, has been named the next director of the MIT Statistics and Data Science Center (SDSC). 

Rakhlin succeeds Ankur Moitra, the Norbert Wiener Professor of Mathematics, associate director of the IDSS, and a faculty member in the MIT Department of Electrical Engineering and Computer Science (EECS) who has been SDSC director since 2021. Philippe Rigollet, the Cecil and Ida Green Distinguished Professor of Mathematics and a core faculty member in IDSS, also served as interim director in 2024-25.

“Sasha is one of the sharpest theoretical minds working in statistics and machine learning today, and also one of the most devoted mentors I know,” says Fotini Christia, the Ford International Professor of the Social Sciences and director of IDSS, which houses SDSC. “He has helped train an entire generation of interdisciplinary scholars through the Interdisciplinary Doctoral Program in Statistics (IDPS), while his own research keeps pushing the boundaries. The SDSC could not ask for a more fitting leader.”

Rakhlin is the inaugural holder of the Distinguished Professorship in Data, Systems, and Society, an endowed chair created in 2025 by the generosity and vision of IDSS professor Richard “Dick” Larson, an “MIT lifer” and pioneer in operations research, queueing theory, and system optimization.

“I am honored to take on this role,” says Rakhlin. “The strength of the Statistics and Data Science Center has always been its people — students, postdocs, and faculty from across MIT who bring sharply different perspectives to the most interesting problems of the day in statistics, machine learning, and AI. My goal is to support that community as it takes on the constantly evolving questions reshaping the field.”

Rakhlin has been connected to the Statistics and Data Science Center as a visiting professor since 2016, before formally joining MIT in 2018 in the Department of Brain and Cognitive Sciences and IDSS. As the initial chair of the Interdisciplinary PhD in Statistics program at the SDSC, Rakhlin has seen the successful defense of over 75 IDPS PhD students across a variety of departments at MIT, including IDSS’ own Social and Engineering Systems program.

“I have been fascinated by machine learning since my PhD work more than 20 years ago, drawn by its beautiful connections to statistics, probability, algorithms, optimization, and game theory,” says Rakhlin. “At the Statistics and Data Science Center, I work alongside colleagues who share this fascination and pursue these connections in many directions. The recent revolution in AI is extending this web into the sciences; it promises to accelerate discovery, and it raises new questions for statistics. Answering them demands a rigorous science of the tools themselves. As AI enters medicine, energy, and public life, its safety and security are, at their core, statistical and mathematical questions: quantifying uncertainty, providing guarantees, understanding failure, and resisting manipulation.”

As Rakhlin puts it, the SDSC is built for this moment. “Statistics is a shared language across MIT,” he adds. “Through the Interdisciplinary Doctoral Program in Statistics, the center connects students and faculty from economics and political science to physics and engineering. Collaborations in areas from biology to nuclear fusion have shown how statistical thinking accelerates science itself.” 

As director, one of his goals is to deepen these interdisciplinary connections. He hopes to help make SDSC the Institute’s home for the rigorous foundations of data science and AI, and a bridge to the scientific and societal questions where those foundations are most needed.

Rakhlin received his bachelor’s degrees in mathematics and computer science from Cornell University, and doctoral degree from MIT. He was a postdoc at the University of California at Berkeley in EECS before joining the University of Pennsylvania, where he was an associate professor in the Department of Statistics and co-director of the Penn Research in Machine Learning center.

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Connecting students with the future of microelectronics

The 2026 Northeast Microelectronics Internship Program (NMIP), organized by the MIT Microsystems Technology Laboratories, brought together 30 exceptional students from leading universities across the Northeast for an immersive week exploring the rapidly evolving world of semiconductor technology and microelectronics. Held July 13-17, the externship provided undergraduate students with an opportunity to experience the complete microelectronics innovation ecosystem, from academic research laboratories to advanced manufacturing facilities.

Throughout the week, students visited several of the region's premier institutions, including MIT.nano, IBM Research, GlobalFoundries, Rensselaer Polytechnic Institute (RPI), and NY CREATES, where they engaged with researchers, engineers, faculty, graduate students, and industry leaders working at the forefront of semiconductor innovation.

The program began at MIT.nano with an inspiring overview of the microelectronics landscape led by Vladimir Bulović, director of MIT.nano, and Farhad Varzhegoo, director of strategic initiatives and partnerships at the Northeast Microelectronics Coalition Hub. Their presentations challenged students to think beyond today's technologies and consider the broader societal impact of tomorrow's innovations.

"What will the next innovation in microelectronics look like, and what should the world of tomorrow focus on?" they asked, encouraging participants to view engineering not only as a technical discipline, but also as a means to solve meaningful real-world challenges.

Following the opening session, Farnaz Niroui, the Emmanuel E. Landsman Career Development Chair and assistant professor of electrical engineering and computer science at MIT, organized a series of graduate student research presentations showcasing the breadth of microelectronics research taking place across MIT. The presentations explored topics spanning integrated circuits, nanoelectronics, photonics, quantum technologies, and advanced materials.

After the student research presentations, participants attended an industry panel exploring the transition from academia to careers in microelectronics. Organized and moderated by Susan Feindt, fellow emeritus at Analog Devices and visiting research scientist at MIT, the panel featured professionals from Rage Systems, Cadence Design Systems, Analog Devices, and RTX (Raytheon), who shared their career journeys, discussed the differences between research and industry, and offered advice on navigating career opportunities in the semiconductor sector.

"What stood out to me most about our day at MIT was the opportunity to engage deeply with PhD students in this field and understand the kind of opportunities available by pursuing a doctoral program," says Shanti Visurakapalli, a current undergraduate student at MIT. "I think this experience, complemented with the industry panel, gave many of us in the program the perspective we needed to weigh future graduate and professional options."

Throughout the week, participants connected classroom concepts with real-world applications through behind-the-scenes access to some of the nation's most advanced research and manufacturing environments. Students explored MIT's interdisciplinary laboratories, observed High-NA EUV lithography and quantum hardware development at IBM Research, toured GlobalFoundries' state-of-the-art 300mm semiconductor fabrication facility, learned how groundbreaking academic research transitions into commercial manufacturing at RPI, and gained insight into next-generation semiconductor fabrication at NY CREATES.

"The externship gave me a behind-the-scenes look at the advanced technologies driving the microelectronics industry while allowing me to connect one-on-one with researchers and industry professionals," says Sean Kim, a student at Princeton University. "Learning about emerging research and receiving career advice broadened my perspective on the field and inspired me to pursue a career in microelectronics."

Beyond the technical experiences, the externship emphasized professional development and networking. Students engaged in meaningful conversations with engineers, scientists, faculty members, and graduate researchers who described their career paths, offered advice, and discussed the many pathways available within the semiconductor industry. These interactions provided participants with valuable perspectives on careers in research, manufacturing, design, and emerging technologies.

"One of the most rewarding aspects of the externship is seeing students from different universities come together around a shared passion for innovation," says Preetha Kingsview, NMIP program administrator. "The friendships they build, the conversations they have with researchers and industry leaders, and the excitement they bring to every visit create an experience that extends far beyond the technical program."

For many students, the experience proved both transformative and inspiring. The opportunity to witness cutting-edge research firsthand while building connections with leaders across academia and industry deepened their understanding of the semiconductor ecosystem and reinforced the critical role microelectronics plays in addressing global challenges.

"For more than half a century, microelectronics has transformed the world, but I believe its most exciting chapter is only just beginning," says Tomás Palacios, the Clarence J. LeBel Professor of Electrical Engineering and Computer Science at MIT and faculty director of the NMIP Program. "From AI and quantum computing to sustainable energy and advanced manufacturing, nearly every technological revolution of the coming decades will be built on advances in semiconductor technology. Today's undergraduate students will become tomorrow's innovators, entrepreneurs, and industry leaders, and programs like the NMIP Externship help inspire and prepare them to shape that future."

By bringing together leading universities, research institutions, and industry partners, the program provides students with a comprehensive view of the semiconductor ecosystem while helping build the highly skilled workforce needed to sustain U.S. leadership in microelectronics.

The 2026 externship demonstrated the power of connecting education, research, and industry. Through a week of laboratory tours and technical presentations, it gave students a firsthand view of how scientific discovery becomes technological innovation — and inspired many to become part of the future of microelectronics themselves.

The NMIP Externship was made possible by the Microelectronics Commons Northeast Microelectronics Coalition Hub and the Microelectronics Commons Northeast Regional Defense Technology Hub (NordTech). Additional support was provided by the MIT Microsystems Technology Laboratories, the MIT Institute for Soldier Nanotechnologies, and the Semiconductor University Research Program for Superior Energy-Efficient Materials and Devices (SUPREME) Center, part of the SRC JUMP 2.0 program.

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Turning molecules into reliable electronic devices

Molecules are among the smallest building blocks available for making next-generation devices. Their unique, customizable properties enable promising applications in emerging computing, sensing, optical, and quantum technologies.

But integrating molecules into functional devices at scale remains a challenge. Traditional semiconductor manufacturing processes can damage small and fragile molecular materials. Now, MIT researchers have developed a scalable fabrication technique that incorporates delicate molecular materials into electronic devices on a chip without causing damage.

Their method extends the capabilities of standard semiconductor manufacturing processes to accommodate molecules. The researchers first prefabricate the device components using traditional processes. Then, they introduce the molecules and harness nanoscale surface forces to mechanically transform the fabricated device, which self-assembles without damaging the molecules. 

The team demonstrated the robustness and scalability of their technique by fabricating more than 1,000 devices using sub-nanometer molecular layers. 

“Our platform combines the scalability of conventional semiconductor manufacturing with the precision and control of self-assembly. This establishes a new fabrication framework for the scalable, high-throughput integration of emerging nanoscale and quantum materials, including molecules, into functional devices with architectures and capabilities that were previously infeasible,” says Farnaz Niroui, an associate professor of electrical engineering and computer science (EECS), a member of the Research Laboratory of Electronics (RLE), and senior author of a new paper describing the work.

She is joined on the paper by co-lead authors Sarah Spector and Peter Satterthwaite, EECS graduate students; Jeremiah A. Johnson, the A. Thomas Guertin Professor of Chemistry at MIT; and others at MIT. The research appears today in Nature Nanotechnology.

Building with molecules

Molecules are small clusters of atoms with structures and chemistries that can be precisely designed. This allows their properties to be engineered across a wide design space.

Once integrated into device architectures, these molecules could enable next-generation electronics and computing platforms that are smaller, faster, and more adaptable, as well as higher-performance photonic devices and emerging quantum technologies.

To build a functional system, molecular building blocks need to be integrated with other device layers. In electronic systems, a critical step is making electrical contacts to the molecules by interfacing them with metallic surfaces. However, the harsh chemicals and processes needed for traditional chip manufacturing damages these fragile molecular materials, reducing reliability and performance.

To leverage the scalability of standard fabrication techniques while achieving the precision needed for handling molecules, the MIT researchers developed a decoupled, two-step approach.

They first fabricate all the device components using standard semiconductor manufacturing, then incorporate the molecular material after-the-fact to finish building the device.

“By bringing the delicate materials into the process only after we have fabricated the main device elements, it allows us to use conventional processes that are normally not compatible with these nanomaterials,” Satterthwaite says.

In their demonstration, the researchers fabricated a scaffold with two metal electrodes separated by a precisely sized gap. Then, they deposited the molecular layer on the electrode surfaces. 

Finally, the researchers leverage nanoscale forces to gently pull the top electrode onto the molecules, forming the final device in a nondestructive way. This creates a self-aligned, damage-free electrical contact to the molecules. 

Using the forces

While gravity is a dominant physical force that holds our world together, different forces dominate at the nanoscale. One, called the capillary force, causes liquid to get sucked into small spaces. (Plants rely on capillary forces to draw water into their stems.) 

By carefully engineering the stiffness of the electrodes, when the solution containing the molecules evaporates, capillary forces gently pull the two metal surfaces together with the molecules sandwiched in between.

Once the two electrodes are in place, the researchers must hold them in a stable state. To do so, they rely on another nanoscale force known as the van der Waals force. 

Van der Waals forces cause surfaces to attract one another. By controlling the device surface area and molecules properties, the researchers ensure these forces will be strong enough to hold the electrodes in a stable structure without damaging the molecules. 

“Nanoscale forces play a critical role in our approach. Instead of fabricating exactly the structures we ultimately want, we make something mechanically mobile and use forces to transform it into an architecture that would otherwise be impossible to fabricate,” Spector explains.

They used this technique to fabricate more than 1,000 devices with molecular layers less than 1 nanometer thick. Even at this tiny scale, the fabricated chips comprised a high yield of working devices, 96 percent on average. The robust devices also endured tens of thousands of electrical cycles without showing any sign of degradation.

“The stability really stands out. This is a critical feature for moving molecular devices toward practical applications, but it has been a persistent challenge in the field,” Satterthwaite says. 

Importantly, this versatile technique allows circuit- and system-level integration of molecular devices, pushing the field beyond the study of isolated devices, the researchers say. They demonstrated this by building an interconnected array of molecular memory devices which could have applications in next-generation computing platforms. 

Their technique can also be extended to other materials and device architectures. 

In the future, the researchers want to build on this platform to investigate and develop new classes of multifunctional computing and sensing devices and systems. 

“By enabling the pristine integration of emerging molecular materials and other atomic-scale matter into functional devices at scale, our platform accelerates discovery and design of these materials with tailored functionalities and their deployment in emerging technologies,” Niroui adds.

This research was funded, in part, by the U.S. Defense Advanced Research Projects Agency (DARPA), the Semiconductor Research Corporation, the U.S. National Science Foundation (NSF), the MathWorks Fellowship, and the Netherlands Organization for Scientific Research. Device fabrication was carried out, in part, using MIT.nano facilities.

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Using reason, again and again

You probably think you are rational. Day to day, you try to “make the best possible use of the information available to you,” as MIT philosopher Brian Hedden PhD ’12 writes in his 2015 book, “Reasons without Persons.” 

If you think you are rational because of how you plan for the future, and change your beliefs over time, however, Hedden will be skeptical. Circumstances change, and when using reason, he thinks, all that matters is the present. Thus, he also writes: “The requirements of rationality should be impersonal, avoiding reference to the relation of personal identity over time.”

This is what Hedden calls “time-slice rationality,” the idea that in applying reason, we exist in little slivers of time and knowledge. There are not permanently reasonable people, just reasonable decisions. 

“We are temporally extended people with hopefully long lifespans, but we’re made up of lots of different time slices,” Hedden says. “So there’s me now, me yesterday, me next year. We should think of the locus of rationality as the time slice, not the temporally extended person.” 

Those past versions of you, Hedden thinks, are like teammates in sports: You are connected to them, but not quite the same person. The payoff from viewing things this way, he contends, is a more streamlined and realistic picture of our thinking. 

“Time-slice rationality” helped launch Hedden’s career. Today he is a professor in MIT’s Department of Linguistics and Philosophy and associate dean for MIT’s Social and Ethical Responsibilities of Computing (SERC) initiative. In a nod to his work, let’s examine some time slices from Hedden’s career.

Falling for philosophy

Hedden grew up in Virginia and attended Princeton University as an undergraduate, where he expected to study electrical engineering. But early on in college, he took some philosophy classes — an introductory course in logic, a history of early modern philosophy — and liked them. A lot. 

“Engineering is still near and dear to my heart, but I really got into philosophy,” Hedden says. 

Almost before he knew it, Hedden had found his primary intellectual interest. Upon graduating from Princeton, Hedden spent a year working for an education nonprofit in Nicaragua, but he had already decided on his next stop: graduate school in philosophy.

That led Hedden to MIT. He wanted to study the philosophy of language, and at MIT, the famous linguistics program is part of the same department as philosophy. Hedden applied to the Institute, was accepted, and arrived on campus eager to pursue his chosen field. 

Lounge life

A funny thing happened to Hedden after he arrived at MIT, however: He stopped studying the philosophy of language. Blame Frank Gehry, the architect. 

MIT’s Department of Linguistics and Philosophy is in the Stata Center, which opened in 2004 and was designed by Gehry to have all kinds of common spaces, including double-height lounges. After Hedden started graduate school at MIT, he got drawn into the philosophical discussions happening in these common areas. Before long, he had changed his intellectual focus. 

“This was largely due to conversations that were happening in the lounge,” Hedden recalls. “The Stata Center has spaces that really encourage collaboration. A lot of people there were talking about puzzles involving probability, epistemology, and decision theory, and I found those things really stimulating, and wound up specializing in those areas. Things wouldn’t be the same if the building were differently arranged.”

Advised by MIT professors Caspar Hare, Robert Stalnaker, and Roger White, Hedden wound up writing his doctoral thesis — three papers — on rationality and decision-making. That formed the basis of “Reasons without Persons,” whose title alludes to a famous work by philosopher Derek Parfit.

While it might seem unusual to draw to draw a distinction between our past, present, and future selves, Hedden thinks we actually do that frequently, in everyday life and cultural work. In Greek mythology, Odysseus rationally chains himself to the mast of his ship, anticipating that his future self will be irrationally unable to resist the call of the sirens.

“That’s a dramatic example, but we do this all the time, like when we buy a gym membership and hope that our future selves will irrationally care about sunk costs and go to the gym to avoid having wasted the money,” Hedden says. 

Heading down under

After earning his MIT PhD, Hedden spent two years as a junior research fellow at Oxford University, then landed his first faculty job in academia — at the University of Sydney, in Australia, in 2015. Five years later, he moved to Australian National University, in Canberra, leaving when he returned to MIT in 2025. 

“I love Australia; I think the quality of life is amazing, the culture is great, the natural world is unbelievable,” Hedden says. The country also has, he observes, “a great philosophy scene,” fed in part by decades of interaction with American scholars. 

Hedden’s work kept evolving during his decade in Australia. He started examining specific, applied topics more often, including many questions about legal processes and evidence. For instance: Should juries even deliberate? In one 2017 paper, Hedden suggested they should not, because, among other things, “deliberation destroys the independence of jurors’ judgments” in ways that can be counterproductive. 

Or: Is there such a thing as “higher-order” evidence, which is evidence about what conclusions your evidence supports? In a 2021 paper, Hedden and now-MIT colleague Kevin Dorst concluded that virtually all evidence fits this billing. 

Hindsight bias: Not bias

Or take another Hedden paper in this vein, from 2019, casting new light on the familiar topic of “hindsight bias.” We often alter our views about things after they happen, which can seem like gratuitous second-guessing. 

Is it, though? Suppose you are investigating a railroad crash and find evidence that a crash was more likely than people imagined. That might simply be useful new knowledge. Suppose your favorite basketball team loses a game, and you reexamine why you thought they would win; perhaps a star player’s injury was more serious than you imagined. Are you changing your basic views, or just conducting a realistic reassessment?

“This is perfectly rational and what we should expect,” Hedden says. “Some people say, ‘Oh, that’s hindsight bias.’ I think it’s just a reasonable conclusion to draw.”

To be sure, in the paper itself, Hedden engages with theoretical philosophical work about evidence and view formation; much of his work bridges academic theory and practical everyday applications. Like many of his papers, this one also evinces the fun of reworking conventional wisdom. 

“I do think that these contrarian views are right,” Hedden says. “But I also find a certain joy in going my own way, or having a skeptical take to get people to rethink views they’re falling into without fully realizing it.” 

After an odyssey, back at MIT

After nearly a decade in Australia, Hedden received an offer to return to one of his intellectual homes: MIT offered him a place on the faculty. Arriving back at the Institute in 2025, Hedden found many things had changed — new buildings on campus, new programs — while some were recognizably the same. 

“The philosophy department looks very similar in terms of the healthy culture,” Hedden says. “It’s always been known as a collaborative, high-energy place with a fantastic graduate program. And it’s really welcoming. That lounge discussion culture is still there. Sometimes cultures can be fragile. There could have been people who let it lapse. But it’s still there, and that’s great.”

Meanwhile, Hedden has added to his intellectual portfolio by becoming associate dean at SERC, a burgeoning initiative at MIT examining a wide range of civic issues around computing. SERC has supported 40 postdocs around MIT since 2022, in all five MIT schools plus the MIT Schwarzman College of Computing. It has also awarded 30 seed grants for faculty research in the last three years.

“There’s been really broad interest from faculty and students,” Hedden says. “I’m interacting a lot with computer scientists especially, but people across the Institute everywhere. The College of Computing is a unifying force.” 

For that matter, the SERC Scholars program had 75 students accepted last fall, from first-year undergraduates to doctoral candidates, working on projects including surveillance, artificial intelligence, the energy impact of the sector, and more. Hedden is also making a point to develop more courses across SERC topics.

“It’s often the younger people, undergraduates and graduate students, the postdocs, the junior faculty, that gives us a constant infusion of new ideas and energy,” Hedden says. “We’re hoping to keep the momentum going.”

In this slice of time, that sounds pretty reasonable. 

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Building energy security through more sustainable batteries

For Hugh Smith, the challenge of building an energy-secure future isn’t about creating the world’s “best” battery. It’s about designing the right battery for the right job.

As a fifth-year PhD candidate in MIT’s Department of Materials Science and Engineering, Smith studies sodium-ion batteries, an emerging alternative to the lithium-ion batteries that power everything from smartphones to electric vehicles. By replacing expensive critical minerals like lithium, nickel, and cobalt with more readily available elements like sodium, iron, and manganese, his research aims to make energy storage both more affordable and more sustainable.

“I’ve believed for a very long time that the biggest engineering problem humanity faces is the transition to clean energy,” Smith says. “Batteries are a critical bottleneck in that transition.”

Growing up in Albany, New York, Smith was drawn to materials science because it combined two of his favorite subjects: chemistry and math. What kept him interested, however, was the field’s ability to touch nearly every aspect of everyday life.

“Anytime you interact with a solid material, there are people who intentionally designed that material for a specific purpose,” he says.

That idea of designing materials with a real-world purpose eventually led him to batteries. After earning his undergraduate degree in materials science from Case Western Reserve University, Smith came to MIT to explore how new battery chemistries could reduce costs without sacrificing performance.

Consumers often want batteries that charge quickly, last for years, store large amounts of energy, and remain inexpensive. But in reality, improving one characteristic of this technology usually means compromising another. A smartphone battery, for example, prioritizes energy density and long lifespan, while a battery storing electricity for the power grid doesn’t need to be lightweight or compact. Instead, cost and reliability become the most important considerations.

Rather than chasing an all-encompassing solution, Smith focuses on finding the right balance for specific applications, often juggling competing priorities. Instead of strengthening a singular characteristic, Smith works to maximize as many components of the battery as possible, including cost, performance, sustainability, and reliability, depending on how it will be used.

“It’s trying to balance everything,” he says. “It’s not catering extremely to some properties and then abandoning others.” 

The sodium-ion batteries Smith studies could eventually provide lower-cost options for electrical grids or more affordable electric vehicles. Because sodium-ion batteries can largely be manufactured using the same infrastructure already developed for lithium-ion batteries, they also offer a potentially smoother path toward commercialization than many emerging battery technologies.

Smith’s graduate school journey has been defined as much by the process of learning how to do research as by the science itself. He joined a brand-new research group at MIT as its first graduate student, and helped establish the lab run by Professor Iwnetim Abate. Without senior graduate students or postdocs to turn to for day-to-day guidance, he often had to teach himself new techniques and how to troubleshoot when things went wrong.

“I learned not to be fearful of new things,” Smith says. “Just because I didn’t know how to do something didn’t mean I couldn’t figure it out.”

He says the experience transformed him into a more independent researcher and someone who is willing to dive headfirst into unfamiliar problems.

Before beginning graduate school, Smith spent seven months at the Battery Innovation Center in Newberry, Indiana, an experience that broadened his understanding of how scientific discoveries become real technologies. Working alongside materials scientists, chemists, mechanical engineers, and chemical engineers showed him that no single discipline can solve the challenges of battery development alone.

“It requires a huge team effort,” Smith says. “It requires a lot of different types of knowledge.”

He says the experience also helped him better understand where his own expertise could make the greatest impact and when collaboration across disciplines is essential.

Outside the lab, Smith makes time to stay active through MIT’s intramural sports program, where he plays soccer, ultimate frisbee, football, and volleyball on teams with fellow graduate students. The games offer a chance to unwind after long days of research while strengthening the friendships he’s built throughout graduate school. He also enjoys fishing around the Boston area with friends and exploring New England’s coastal towns, museums, and historic sites.

As he prepares to graduate in the winter and pursue a career in battery research and development, Smith hopes to continue designing technologies that support the transition to clean energy. 

“Lots of smart people have already made wind and solar very cheap,” Smith says. “The issue is reliability, and batteries can help solve that problem. I hope the work I’m doing helps to affordably unlock the transition to an electric grid powered by reliable clean energy, and an electrified transportation network.”

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Connecting research to policy on Capitol Hill

This spring, 25 MIT students and postdocs traveled to Washington to meet with congressional staffers and advocate for sustained federal investment in scientific research. 

With recent cuts to National Science Foundation programs and continued uncertainty surrounding the federal research budget, these conversations were especially timely. Over the course of just two days, participants met with 62 congressional offices representing 32 states to discuss the importance of federal support for scientific research, higher education, and other policy concerns related to their individual research areas.

Each spring, the MIT Science Policy Initiative (SPI) organizes Congressional Visit Days (CVD), a program that introduces graduate students and postdocs to the federal policymaking process while demonstrating the many ways scientists can engage in policy advocacy. In addition to meeting with congressional offices, participants connect with Washington-based MIT alumni and members of the MIT Washington Office to learn about careers at the intersection of science and public policy.

This year's CVD was co-organized by Audrey Parker, a PhD student in civil and environmental engineering at MIT, and Ian Robertson, a PhD student in physical oceanography at MIT and the Woods Hole Oceanographic Institution (WHOI). Robertson reflects on the experience:

"Having attended the trip as a participant last year, stepping into the role of a co-leader this year was a big commitment that was well worth the payoff. It was rewarding to build on the work of past leaders, strengthening the CVD experience for participants by training and encouraging them to discuss not just general science funding advocacy in their meetings, but also specific policies tied to their research. I look forward to the future success of the CVD program in continuing to provide students and postdocs a template for science policy conversations with Congress and helping them realize the various avenues in which they can connect research to policy throughout their careers."

To prepare for the trip, participants attended three training sessions led by SPI in collaboration with the MIT Washington Office and the MIT Policy Lab. These sessions provided background on the federal appropriations process, the role of congressional staff in shaping legislation, and practical strategies for communicating scientific expertise to policymakers. The training sessions also gave participants a chance to practice sharing their research and policy pitches with each other in mock "Hill meetings."

While on the Hill, students advocated for both general science funding for the upcoming fiscal year as well as specific policies tied to their research in artificial intelligence, environmental science and engineering, energy, space, and health. They encouraged offices to edit language in bills, support bills already on the floor, or sponsor new bills. Staffers on both sides of the aisle were particularly interested in discussing AI privacy and security across disciplines. They also expressed strong interest in hot environmental topics, such as deep-sea mining, and were eager to learn more about its associated environmental consequences. In many cases, conversations about participants' research and science-based policy priorities reinforced the need for continued federal funding of science, enabling staffers to connect abstract funding decisions with the researchers and projects they support.

The experience proved valuable for both the MIT delegation and the congressional offices they visited. Rodrigo Zuniga, a first-year PhD student participant, highlights:

"Going to Washington, D.C., offered a whole new perspective of the role of science in politics for me. In today's news and social media landscape, it's really easy to see Washington as irreversibly polarized, but in talking to staffers from both the majority and minority parties, I saw a general desire for bipartisanship and widespread support for science. What's most clear to me after this experience with CVD is that there is a lot of room and pressing need for humans with scientific training and expertise to participate proactively in local, state, and federal government."

As scientific and technological issues continue to shape public policy, opportunities for researchers to engage with policymakers have never been more important. Programs like Congressional Visit Days help equip the next generation of scientists with the knowledge and confidence to communicate the value of research beyond the laboratory, strengthening connections between the scientific community and the policymakers whose decisions shape its future.

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Why some nitrogen-processing enzymes are more efficient than others

Nitrogen gas is abundant in Earth’s atmosphere, but most living organisms can’t readily use this nitrogen. Only a subset of microbes that have enzymes known as nitrogenases can break nitrogen gas apart and convert it into ammonia.

There are three different classes of nitrogenases found in nitrogen-fixing microbes, which vary based on the types of metal that they contain. Nitrogenases that contain the metal molybdenum are the most efficient, and two new studies from MIT offer an explanation for why that is.

The findings could help guide the design of engineered enzymes or synthetic catalysts that can convert nitrogen gas to ammonia, the researchers say.

The team found that while molybdenum doesn’t directly bind to nitrogen, it helps nearby iron atoms bind to nitrogen more strongly. This is a critical first step in breaking the bond between the two nitrogen atoms that form nitrogen gas.

“It’s that initial binding step that’s really the hard part. Once you’ve started to break the nitrogen-nitrogen triple bond and make some new nitrogen-hydrogen bonds, it’s pretty easy to get the rest of the way,” says Daniel Suess, the Arthur Amos Noyes Associate Professor of Chemistry at MIT and a senior author of both papers.

MIT postdoc Tong Wu and former postdoc Madeleine Ehweiner are the lead authors of one of the papers, and Alexandra Brown PhD ’23 is the lead author of the other. Kyle Lancaster, a professor of chemistry at Cornell University, is a senior author of the latter paper, along with Suess. Both papers appear today in the journal Chem.

Efficient enzymes

Before microbes evolved the ability to fix nitrogen around 3 billion years ago, the strong triple bond between atoms of N₂ could only be split with high-energy events such as a lightning strike.

“Once an enzyme came along that could convert dinitrogen to ammonia, that changed the game because now cells could harvest nitrogen from the air for biomass,” Suess says.

Within the active site of nitrogenase is a catalytic cofactor that typically consists of a cluster of iron, sulfur, carbon, and in some cases another metal. Nitrogenases whose cofactors contain molybdenum are the most efficient, followed by those containing the metal vanadium. Nitrogenases that don’t have any metal other than iron are the least efficient.

Why the molybdenum-containing enzyme is more efficient has been a puzzle, especially because it’s thought that molybdenum itself doesn’t bind directly to nitrogen gas.

“In all cases, iron is thought to interact with N₂, so it’s a bit of a mystery,” Suess says. “If all the chemistry is happening at iron, why is it that this molybdenum is affecting catalysis?”

To answer that question, Suess’s lab has developed simpler versions of iron-sulfur clusters that they can use to model the naturally occurring cofactors. These can be modified by adding different metal atoms, allowing the researchers to study how those metals change the cofactors’ properties. 

In the first paper, led by Wu and Ehweiner, the researchers swapped in different metal atoms and then measured the ability of the iron in the cofactor to bind to nitrogen. They found that only cofactors with a large metal atom, such as molybdenum or tungsten, were able to strongly bind N₂. With vanadium,  chromium, or iron, which are smaller, the cofactors did not bind N₂ and performed other reactions instead.

“That paper essentially recapitulates what you see in biology, which is that the iron-sulfur clusters that have molybdenum in them seem to be better at binding dinitrogen than those with lighter metals,” Suess says.

Sharing electrons

In the second paper, led by Brown, the researchers uncovered a possible mechanism that explains that phenomenon. 

In that paper, the researchers studied how cofactors containing different metals interact with compounds called N-heterocyclic carbenes. These molecules behave similarly to N₂ in some ways, making them a good model for this type of study. Like N₂, they are resistant to accepting any electrons from another molecule, which is an essential step to breaking chemical bonds. 

The researchers found that when molybdenum was included in the cluster, it became easier for iron to donate some of its electrons to the N-heterocyclic carbenes, in a process known as back-bonding. This occurs because molybdenum, a large atom, has large orbitals that can overlap with the orbitals of the nearby iron atom. That alters iron’s electron density in ways that make it easier for iron to pass electrons to N₂.

“Without these direct metal-metal interactions, the iron has to do all the work, but adding the molybdenum allows for this electronic cooperativity,” Suess says.

Once N₂ is bound to an iron atom, the rest of the reaction can proceed. A proton can come in from water or another source to create an N-H bond, which then makes it much easier for the remaining N-N bonds to be broken and bind to protons, forming NH₃. 

The findings could help guide scientists who are working on designing enzymes that could be engineered into organisms that help them generate their own NH₃, eliminating or reducing the need for fertilizer. The results could also help chemists to design synthetic catalysts that could produce ammonia industrially, using less energy than the Haber-Bosch process. 

“The general principle is that you can make an iron site in any context behave differently when you have these metal-metal interactions than when you don’t have these interactions,” Suess says. “The primary result of these findings is to teach us about the natural world and how nature accomplishes this really important and miraculous reaction. And, maybe that can be translated into new processes.”

The research was funded primarily by the U.S. Department of Energy, the National Science Foundation, and the National Institute of General Medical Sciences.

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