Atomic electron tomography: 3D structures without crystals
Abstract
To understand material properties and functionality at the most fundamental level, one must know the three-dimensional (3D) positions of atoms with high precision. For crystalline materials, x-ray crystallography has provided this information since the pioneering work of Max von Laue, William Henry Bragg, and William Lawrence Bragg around 100 years ago. But perfect crystals are rare in nature. Real materials often contain defects, surface reconstructions, nanoscale heterogeneities, and disorders, which strongly influence material properties and performance. Completely different approaches from crystallography are needed to determine the 3D atomic arrangement of crystal defects and noncrystalline systems. Although single-particle cryo–electron microscopy (cryo-EM) has been under rapid development for 3D structure determination of macromolecules with identical or similar conformations at near-atomic resolution, this method cannot be generally applied to the physical sciences for the following three reasons. First, most materials do not have identical copies and cannot be averaged to achieve atomic resolution. Second, a priori knowledge of the peptide sequence and stereochemistry in protein molecules greatly facilitates their 3D atomic structure determination, but this knowledge is not applicable to physical science samples. Third, unlike in biological specimens, the presence of diffraction and phase contrast in the transmission electron microscopy images of most materials poses a challenge for tomographic reconstruction.These difficulties have made the objective of solving the 3D atomic structure of crystal defects and noncrystalline systems a major challenge for structural characterization in the physical sciences.
Document Details
- Document Type
- Pub Defense Publication
- Publication Date
- Sep 23, 2016
- Source ID
- 10.1126/science.aaf2157
Entities
People
- Jianwei Miao
- Peter Ercius
- Simon Billinge
Organizations
- Brookhaven National Laboratory
- Columbia University
- Defense Advanced Research Projects Agency
- Lawrence Berkeley National Laboratory
- National Science Foundation
- Office of Basic Energy Sciences
- Office of Naval Research
- United States Department of Energy
- University of California, Los Angeles