Fig. 13.
HRTEM image typical for a less densely packed area of the A7-pVIII directed ZnS nanowire. In such less densely packed area, the nanocrystals were not overlapped, but were isolated and could be resolved by HRTEM lattice imaging, and a preferred orientation was determined through their digital diffractograms. Therefore, digital diffractograms from individual nanocrystals were readily obtained, and ab-plane misorientation was analyzed statistically. At least 11 nanocrystals were visible and numbered (Insets). The digital diffractograms of these nanocrystals showed that they were preferentially oriented with c-axis perpendicular to the viral surface, but with slight misorientaion in ab plane. Nanocrystal i was chosen as a standard pattern indexed with [001] zone axis. The (110) reflection was chosen to estimate the ab-plane misorientation. Based on crystallographic symmetry, the direction of (110) reflection of each nanocrystal can be determined from other reflections if the (110) reflection is not clearly visible. The angle (α) between the horizontal line of the image and the (110)-(000) connection line was measured for every nanocrystal. For nanocrystals a-k, the α value was 36.9, 46.7, 43.6, 56.7, 50.4, 53.8, 48.1, 47.6, 58.0, 58.7, and 30 degrees, respectively. Then a standard deviation (σ) of α was calculated to be 8.9° , representing the degree of misorientation in ab plane.