Figure 5.

Contour plots of GISAXS scattering projection integrations taken during first compression (A), first decompression (B), and second compression (C) cycles of 7.14 nm diameter Fe₂O₃ nanocrystals at the air–water interface. The film was compressed and then decompressed at 0.5 mm/min with scattering images taken approximately every 10 sec. The film was compressed from a surface coverage of 0.72 to 1.2, however scattering beyond a surface coverage of 0.95 (not shown) resulted in blocking of the X-ray beam by the moving barrier. (D) Plot of edge-to-edge separation vs. surface coverage during the first compression (■), first decompression (♦), and second compression (▲) cycles. Calculation of the edge-to-edge separation was determined from the peak position of the {10} Bragg rod.