Table of Contents
Small-angle X-ray scattering (SAXS)
Small-angle X-ray scattering probes the material over very low spatial frequencies. This allows observations of inhomogeneity or periodicity in the density, which can be particularly useful for identifying microphase segregation or mesoporosity. It also can give information about domain morphology and size, for example, of small nanoparticles, when crystallites are sufficiently dilute.
Key advantages:
- Provides high-resolution scattering data at low angles to capture low-frequency structural properties
- Helps to analyze very large crystal structures such as nanoparticle superlattices.
- Provides information about density fluctuations such as from microphase segregation or mesopososity
- Probes particle shape and size, independent of the internal structure for particles in suspension
Target information:
- Microphase segregation: density fluctuations from segregated components that are not thermodynamically compatibles, e.g. in paracrystalline polymers.
- Long period: distance between like-density domains, e.g. in polymers
- Mesoporosity: density fluctuations from pore structures; e.g. porous carbons: help to identify interparticle correlations
- Interdomain periodicities: identify periodic arrangements of particles or domains distributed in a matrix
- Nanoparticle superlattice structure: unit cell, structural symmetry, and nanoparticle positions.
- Particle size and shape: determined from particle form factor analysis for particles in suspension, complementary to HR-XRPD analysis of crystallites
- 1D and 3D radial distribution function determination: Fourier analysis of small-angle data, analogous to TS-PDF methods except access structural correlations on much lower spatial frequencies
- Form factor fitting: fitting of particle shape factors