Structure determination of Pt-coated Au dumbbells via fluctuation X-ray scattering.
A fluctuation X-ray scattering experiment has been carried out on platinum-coated gold nanoparticles randomly oriented on a substrate. A complete algorithm for determining the electron density of an individual particle from diffraction patterns of many particles randomly oriented about a single axis is demonstrated. This algorithm operates on angular correlations among the measured intensity distributions and recovers the angular correlation functions of a single particle from measured diffraction patterns. Taking advantage of the cylindrical symmetry of the nanoparticles, a cylindrical slice model is proposed to reconstruct the structure of the nanoparticles by fitting the experimental ring angular auto-correlation and small-angle scattering data obtained from many scattering patterns. The physical meaning of the refined structure is discussed in terms of their statistical distributions of the shape and electron density profile.
Physical Bioscience Division, Lawrence Berkeley National Laboratories, Berkeley, CA, USA.
Gang
G
Chen
Miguel A
MA
Modestino
Billy K
BK
Poon
André
A
Schirotzek
Stefano
S
Marchesini
Rachel A
RA
Segalman
Alexander
A
Hexemer
Peter H
PH
Zwart