Packard Fellowship to build spectrometer to analyze molecules in 3-D

(Nanowerk News) Junrong Zheng's techniques to see the fine details of how molecules interact have earned the young Rice University scientist a highly prestigious Packard Fellowship.
Zheng and his team of postdoctoral researchers and graduate students will use the five-year grant that comes with the fellowship to build a laser-based spectroscopic device to easily see the conformation -- the shape and orientation -- of any molecule, no matter how complex.
Junrong Zheng, Rice University
Rice University chemist Junrong Zheng will use his Packard Foundation award to build a spectrometer that can determine the conformation of molecules in three dimensions.
Zheng, an assistant professor of chemistry who joined Rice in 2008, discovered a method to analyze the natural vibrations of the bonds that hold molecules together in a way that can tell him how far apart those molecules are. Further work led to a 2-D method for finding the angles at which the atoms within a molecule bond.
Now Zheng is preparing to leap into real-time, three-dimensional analysis of molecular conformations. Doing so will take some time and effort -- and money -- to build a machine capable of looking at molecular details in a way nobody has before. A successful effort could mean a quantum leap in the study of chemical reactions, protein folding, drug/protein interactions, doped nanomaterials and molecular recognition.
Zheng anticipates it will take five years to build the machine, a full-spectrum, multidimensional spectrometer that can read a wide range of frequencies from the high infrared to the low terahertz. It will allow researchers to take snapshots of molecules that could provide in seconds data that now takes days to acquire.
He knows firsthand about that process; he published a paper this year that detailed his technique for acquiring 3-D data from a specific molecule.
The paper in the Journal of Physical Chemistry ("Mapping Molecular Conformations with Multiple-Mode Two-Dimensional Infrared Spectroscopy") described how Zheng and his team analyzed the conformations of a small molecule, 1-cyanovinyl acetate, known to contain a wide range of vibrational energy.
Theoretical calculations of the five possible conformations of the molecule let them compare what they saw through physical analysis with a two-dimensional infrared spectrometer designed by Zheng and his team. The comparison showed theory and experimental results in virtually perfect alignment.
Zheng believed results for molecules bigger than the fast-moving 1-cyanovinyl acetate would be just as good because their rotations are slower.
Zheng said the machine, when finished, will probably be the only one of its kind in the world. The goal is the development of a sophisticated yet routine analytic tool for determining molecular structure for chemists and researchers who are not laser specialists.
"Hopefully, we can make it very easy to use, so everybody can go buy one," he said.
The David and Lucille Packard Foundation names 16 award winners every year from among 100 nominees who represent 50 American research universities. Zheng is the fifth Rice researcher to win. He joins Rice physicists Thomas Killian and Douglas Natelson and Earth scientists Cin-Ty Lee and Rajdeep Dasgupta.
"I didn't anticipate this award, because I know some very important people in our field have won it," Zheng said. "I know it's very competitive, so it means people appreciate my work."
Source: Rice University