It is hard to imagine just how small one nanometer—one-billionth of a meter—really is. Ten hydrogen atoms in a row are one nanometer long. For perspective, consider that a sheet of paper is 75,000 nanometers thick. A red blood cell is 7,000 nanometers across. A typical virus is about 100 nanometers wide, and a strand of DNA is two nanometers wide.
To see at the atomic and molecular scale, scientists use instruments such as atomic force microscopes that “feel” surfaces with a mechanical probe, electron microscopes that scan a highly focused beam of electrons across a sample, and x-ray scattering instruments that direct x-rays at a sample surface. With these instruments, scientists can probe the crystal structure, chemical composition, and electronic nature of materials. Understanding these properties is key to designing and optimizing materials with the desired functions for particular applications.
However, modern-day experiments are producing data of a highly complex and abstract nature. Thus, data interpretation can be difficult.
“We have some exquisite methods for reconstructing three-dimensional (3-D) structures at the nanoscale,” said physical chemist Kevin Yager, leader of the Electronic Nanomaterials Group at the Center for Functional Nanomaterials (CFN)—a U.S. Department of Energy (DOE) Office of Science User Facility at Brookhaven National Laboratory. “But even if you’ve measured the structure perfectly, you haven’t learned anything until you understand how the components are organized. New visualization and sonification methods can really help provide this understanding.”

Data sonification

Over the past several years, Yager and Margaret Schedel—an associate professor in the Department of Music at Stony Brook University (SBU), where she is also the co-director of the computer music program and an affiliate faculty member at the Institute for Advanced Computational Science—have been combining their expertise to convert x-ray scattering data of nanomaterial structures into sound. To capture these data, Yager uses the Complex Materials Scattering and Soft Matter Interfaces beamlines at the National Synchrotron Light Source II (NSLS-II), another DOE Office of Science User Facility at Brookhaven Lab. These two beamlines are partner instruments jointly operated by the CFN and NSLS-II.

“I knew that Kevin shoots x-rays at nanoparticles to understand their structure but spends most of his day programming computers,” said Schedel. “One day, I asked him how it all works. He said that x-rays bounce off the atoms in a sample and are recorded by a detector. From that scattering pattern, he can compute the structure of the material with the fast Fourier transform (FFT) algorithm. He started explaining what FFT is, but I stopped him because it is the same algorithm that I use all the time in my computer music work.”

Image Credit:  YouTube

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