Pathfinders

Have you ever shot an electron beam through a molecule? Undergrads in Ken Hedberg's lab take aim and discover how matter is arranged.

Robert Johnson gets a lot of strange looks when he tells his friends what he does in Ken Hedberg’s lab. The senior from Salem and another student, Luke Costello from Corvallis, shoot beams of electrons through clouds of gasses and use the results to analyze molecular structure.

“People ask ‘why?’” says Johnson. “I just say, ‘because it’s interesting to me.’ It’s so simple,” he adds, as though he were taking snapshots at the beach, “but you get a lot of information out of it about the molecules.”

Ken Hedberg advises undergraduates Robert Johnson, right, and Luke Costello. (Photo: Karl Maasdam)

Ken Hedberg advises undergraduates Robert Johnson, right, and Luke Costello. (Photo: Karl Maasdam)

For Johnson and Costello, there’s more to it than personal interest and curiosity. They’re solving problems — troubleshooting equipment, puzzling over data with Hedberg, running numbers, reporting results — on their way to bachelor’s degrees in chemistry at Oregon State University. They both plan to attend graduate school and to pursue research full time, Johnson in chemistry and Costello in material science.

Every good coach, whether in baseball or chemistry, focuses on the fundamentals. Hedberg shows his students how to transform solid materials into gasses, generate and guide an intense electron beam the width of a human hair through the gas, record the resulting “diffraction pattern” and use the results to calculate the distances between atoms that define the size and shape of the molecule. To get on base, Costello and Johnson run samples to make sure the machinery is working properly. Convincing evidence of the shape of a complex molecule is a home run.

Hedberg, an OSU alumnus (Chemistry, ’43) and emeritus professor, explains further: “The energy of the electron beam we use is so great that it passes right through the atoms, looks at the nucleus and gets bent around the nucleus. And as these electron waves pass through, they interfere with each other and create a diffraction pattern. That diffraction pattern is what we analyze to determine the structures of the molecules in the gas phase.”

Since he came to OSU in 1956, Hedberg and his students have explored a library of compounds — halides and butadienes, diboranes and cyclohexanes. Unless you’re a chemist, you probably wouldn’t know a halide from an oxide, but in 1993, he and his team were the first to confirm and publish the structure of a newly discovered soccer-ball shaped molecule that had made the headlines: carbon 60, aka the “buckeyball.” Hedberg’s analysis of carbon 60 in the gas phase turned out to be more accurate than studies of its solid form.

In past generations, you would have been hard pressed to find undergrads doing this kind of work. Original research — studies that push the edge of current theory and practice and contribute new knowledge — used to be the domain of graduate students, post-doctoral researchers and the faculty. Undergrads had to get through the basics before they were admitted to the inner sanctum of the lab.

At OSU, as at colleges and universities around the country, Johnson and Costello are part of a movement, undergrads who conduct independent research and original creative work as part of their academic programs. It’s not learning by listen and repeat-after-me. It’s about jumping in with both feet, curiosity-based inquiry under the guidance of people who have been there and remember the thrill of creating something new. In the process, students learn about themselves — their skills, personal goals and career interests — as much as about atoms, the arts, the environment, human health, technology and other fields.

“Independent research teaches you how to work things out yourself and not have somebody hold your hand the whole way,” says Costello, who nevertheless appreciates the supportive, close-knit atmosphere he’s found in the OSU chemistry department. “I have friends who are in big labs elsewhere and end up watching other people’s experiments or doing total grunt work. They’re not doing the actual experimental work.”

Knowing how molecules are shaped, says OSU emeritus professor Ken Hedberg, leads to understanding how they function. (Photo: Karl Maasdam)

Knowing how molecules are shaped, says OSU emeritus professor Ken Hedberg, leads to understanding how they function. (Photo: Karl Maasdam)

And besides, he says, “Ken Hedberg’s a great guy to work for.”

Independence and ownership — what Susie Brubaker-Cole, associate provost for academic success and engagement, calls “a feeling of agency” — define this activity. So does mentorship. In teams or one-on-one, faculty members instruct and guide undergrads through the process of asking questions, designing experiments, analyzing data and creating presentations. This “learning community” of undergraduate and graduate students, post-doctoral researchers and faculty members can become a student’s family away from home, adds Brubaker-Cole. And the faculty link today’s students to academic traditions and culture. In Hedberg’s case, that legacy includes another stellar OSU alumnus, Linus Pauling.

Job on the Home Front

Hedberg grew up in southern Oregon and graduated from Medford High School. In 1943. with an OSU chemistry degree in hand, he went to work for the research arm of the Shell Oil Co. in California on aviation gasoline, synthetic rubber and penicillin extraction, projects deemed crucial to the war effort.

After earning his Ph.D. in physical chemistry and working as a post-doctoral researcher at Caltech, Hedberg came to OSU with strong encouragement from Pauling. OSU Chemistry Professor Earl Gilbert had made a second job offer to Hedberg that spring (Hedberg turned him down the first time), and the young chemist sought Pauling’s advice. One evening, on the veranda of Pauling’s Pasadena home, the Nobel Prize winner urged Hedberg, already an expert in the analysis of molecules by electron diffraction, to accept.

After he came to OSU, Hedberg maintained his friendship with Pauling, and with nearly continuous National Science Foundation support for his research since 1962, he depended largely on graduate students to help him with studies in molecular structure. Although he retired in 1987 and turned 91 in February, the emeritus professor of chemistry continues to work nearly every day in his office and plays an occasional game of tennis. “My wife Lise says she is retired and knows it and that I am retired and don’t know it,” says Hedberg.

Meanwhile, his NSF grants have shifted to support for undergraduates like Costello and Johnson. “They are doing much the same kind of work that my graduate students used to do. It’s lots of fun. These kids are bright, and for the most part, they have been quite interested and productive,” he says.

His goal, he wrote in a 50-year retrospective published in the journal Structural Chemistry, is always to answer a simple question: “Why are things the way they are?” In 2005, after more than five decades of seeking answers through chemical structure, Hedberg traveled to Ulm University in Germany to receive one of the highest honors in his field: the International Barbara Mez-Starck Prize, given to scientists who have made outstanding contributions to structural chemistry.

In addition to his achievements, Hedberg brings something else to his role as a student mentor. Virginia Cross, a 1972 OSU chemistry alumna, recalls that Ken and his wife Lise, a chemist and computer programmer who wrote analytical software for the lab, made students feel welcome. “It was a little family down there in the basement in the chemistry building,” she says. “He respected you to the point of saying ‘what do you think about this?’ He would ask for your opinion even if he could have just told you what he thought. And he was interested in your life, not just the science.”

Cross was a forerunner of today’s trend in undergraduate research. With support from NSF, she spent the summer of her junior year in Hedberg’s lab analyzing sulfuryl fluoride (a pesticide). Success in determining its structure helped her get into graduate school at MIT and led to a paper in the Journal of Molecular Structure on which she was co-author with Norwegian chemist Kolbjørn Hagen and Hedberg.

Currently a resident of Houston, Cross grew up on a dairy farm near Hillsboro, Oregon, and worked in the chemical industry and, until her retirement in 2010, with Richard Smalley, discoverer of the “buckeyball” molecule and a Nobel Prize winner. She has stayed in touch with Hedberg over the years.

National Imperative

Three years before Cross graduated from OSU, MIT created the country’s first campus-wide undergraduate research program. Over the next two decades, Caltech followed suit, the NSF spurred new opportunities with a Research Experience for Undergraduates program and a national conference for undergraduates got under way. That annual event continues to attract student presenters from the sciences, engineering, the humanities and the arts.

At OSU, student opportunities have grown along with the university’s research portfolio, which has more than doubled in the last decade. Little university-wide data is available (monitoring student participation is left to each faculty member, department and college), but personal discoveries are shaping today’s undergraduates in ways their parents could have hardly imagined.

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