Sample interview questions: How do you approach the characterization of materials at the atomic or molecular level?
Sample answer:
Characterization Techniques at the Atomic or Molecular Level:
-
X-ray diffraction (XRD): Determines crystal structure, phase composition, and lattice parameters. Provides information about atomic bonding and arrangement.
-
Transmission electron microscopy (TEM): Images individual atoms and molecules, revealing morphology, composition, and defects. Allows for high-resolution structural analysis.
-
Scanning tunneling microscopy (STM): Maps the surface topography of materials at the atomic level, providing information about surface structure, defects, and electronic properties.
-
Atomic force microscopy (AFM): Measures surface topography, detects forces between atoms, and manipulates individual atoms. Provides insights into surface morphology, mechanical properties, and intermolecular interactions.
-
Scanning probe microscopy (SPM): Includes techniques such as STM and AFM, which allow for surface profiling, nanostructure characterization, and nanoscale manipulation.
-
Spectroscopy techniques:
- X-ray photoelectron spectroscopy (XPS): Provides information about surface elemental composition, chemical states, and electronic structure.
- Auger electron spectroscopy (AES): Similar to XPS but with higher surface sensitivity, revealing details about surface layers and interfaces.
Read full answer