Angular correlations of photons from solution diffraction at a free-electron laser encode molecular structure

Mendez, D.; Watkins, H.; Qiao, S.; Raines, K.S.; Lane, T.J.; Schenk, G.; Nelson, G.; Subramanian, G.; Tono, K.; Joti, Y.; Yabashi, M.; Ratner, D.; Doniach, S.

doi:10.1107/S2052252516013956

Figure 5
CXS of the {111} Bragg ring simulated for single- and multi-domain NP models. (a) The simulated CXS for a non-twinned cuboctahedron gold NP atomic model (section S2 in the supporting information). Note that, for single-domain gold particles, one would only expect a CXS signal at cosψ = $[\pm {1\over 3}]$ , corresponding to the {111} interplanar angles of an f.c.c. crystal. We observed this CXS signal from the large domains in our sample. (b) The simulated CXS for a nearest-neighbor tetrahedron (NNT, outlined in dashed blue). Multi-twinned particles, such as the decahedron shown here, are composed of several NNT units. The angular gap in the decahedron results because the tetrahedra are each close-packed f.c.c. domains (Yang, 1979