Karena Chapman 

Vitals

Current Affiliation: Argonne National Laboratory

Age: 35

Ph.D. alma mater: University of Sydney

Role model: Chapman chose acquaintance Clare P. Grey, a materials chemist at the University of Cambridge: “She undertakes careful and thoughtful experiments to address important fundamental questions while also serving as a great mentor who is always willing to make time to talk science or give advice.”

In a world without chemistry, I would be: a musician, an architect, or a writer. “Finding the best design or composition seems immensely satisfying.”

Codename: X-ray Manipulator

Figuring out how complex materials work—and then making them work better—often requires exposing the chemical secrets hidden deep inside.

Getting a close view of a material’s atomic structure helps scientists see how a drug hits its target, reveal how a lobster’s shell forms, or learn about the super-fast chemical reactions inside a cordless drill battery.

But the ability to capture that level of detail is extremely rare. Not only can Karena Chapman do it, she helps other scientists do it too. She is in charge of the high-energy X-ray beamline at Argonne National Laboratory and has spent the past decade developing its capabilities.

Researchers from around the globe bring their samples—zeolites, battery electrodes, nanoparticles, and pharmaceuticals—to the world-class synchrotron facility at Argonne to learn how, when, and where atomic bonds form and how chemical reactions proceed under real-world pressures and temperatures.

Answering those questions is worth traveling for. As a grad student doing crystallography in Australia, Chapman jumped at the chance to conduct short bouts of experiments at Argonne. The facility is in high demand, so visiting researchers who’ve managed to secure a time slot to use the beamline are under pressure to make the most of their 36 or 48 hours of access by revising their experiments on the fly. “It’s science for adrenalin junkies,” she says.

That scientific rush brought Chapman back to Argonne for a postdoc in 2005. She never left. Now a leading materials researcher, she has made discoveries about how high-power electrode materials work and ways to manipulate and improve gas-capturing metal-organic framework compounds.

In her collaborations with other scientists, Chapman dives in when an experiment needs finesse and will push the boundaries of what the beamline can do, says John Parise, professor of geosciences at Stony Brook University. “She is very clever at designing experiments and has a passion to get results. Everyone wants to come work with Karena.”

Research at a glance

Among the many materials Chapman has studied with Argonne’s high-energy X-rays are metal-organic framework (MOF) compounds. She discovered that at increasing pressures, a particular MOF can trap radioactive I2 gas. To monitor this type of transition, she measures the X-rays scattered from the sample, plotting the data as a pair distribution function (top right). The colors in the graph indicate the probability of finding atoms separated by a given distance, and peaks correspond to observed bond lengths. Credit: Karena Chapman/Argonne National Laboratory/C&EN

Among the many materials Chapman has studied with Argonne’s high-energy X-rays are metal-organic framework (MOF) compounds. She discovered that at increasing pressures, a particular MOF can trap radioactive I2 gas. To monitor this type of transition, she measures the X-rays scattered from the sample, plotting the data as a pair distribution function (top right). The colors in the graph indicate the probability of finding atoms separated by a given distance, and peaks correspond to observed bond lengths. Credit: Karena Chapman/Argonne National Laboratory/C&EN

Three key papers:

“Comprehensive Insights into the Structural and Chemical Changes in Mixed-Anion FeOF Electrodes by Using Operando PDF and NMR Spectroscopy” (J. Am. Chem. Soc. 2013, DOI: 10.1021/ja400229v)

“Exploiting High Pressures to Generate Porosity, Polymorphism, And Lattice Expansion in the Nonporous Molecular Framework Zn(CN)2” (J. Am. Chem. Soc. 2013, DOI: 10.1021/ja4012707)

“Pressure-Induced Amorphization and Porosity Modification in a Metal-Organic Framework” (J. Am. Chem. Soc. 2009, DOI: 10.1021/ja908415z)

 

Career paths:

They might be young scientists, but our Talented 12 have already traveled far and wide.

karena_chapman_map

 

Watch Chapman talk about her research during a special Aug. 22 Talented 12 symposium held at the American Chemical Society national meeting in Philadelphia.

Luis Campos
Anthony Estrada 
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