Figure 2 BF and HRTEM images of approximately 110° kinks in diffe

Figure 2 BF and HRTEM images of approximately 110° kinks in different NWs. (a, c, e) BF images of 110° kinks. Insets in (a) and (c) are SAED patterns corresponding to the selected areas. Clear contrast changes are indicated by white arrows in (e). (b, d, f) are HRTEM images corresponding to the selected areas in (a), (c), and (e) separately. SFs are observed in the kink

area in (b). In (d), SFs and twins are shown in the KU-60019 cost adjacent region to the kink. Large numbers of SFs are observed along the growth direction shown in (f), while twins were observed in the kink area. Compared with approximately 110° kinks, the approximately 70° kink bends sharply as shown in Figure 3a. Its corresponding SAED pattern (inset) matches well with cubic zinc blende structure, and the lattice planes are 111 planes. As shown in Figure 3b, the nanotwin appears in the bending area, which is similar to

that occurs in approximately 110° kinks. As mentioned above, the formation of nanotwin could be beneficial to the change of growth direction. In addition, it is worth noting that highly dense SFs are also observed in the approximately 70° kink area and nearly parallel to the growth direction. In such a sharp bending, the strain is so severe, which could produce the internal stress larger than that in approximately 110° kink. Figure 3 BF image with corresponding SAED pattern and HRTEM image of approximately 70° kink in InP NWs. (a) BF image of approximately 70° kink in InP NWs. The SAED pattern from the kink area (inset) matches with Atorvastatin cubic zinc blende structure.

(b) HRTEM image of the selected region in (a). Dense SFs indicated by white arrows emerge in the kink area. The twin indicated by TB appears in the kink area. On the basis of the above observed results, approximately 70° and 110° kinks are believed to form by the glide of 111 planes, which produces nanotwins and SFs to facilitate the formation of such kinks. It is known that 111 planes are the closest packed planes with the lower interfacial energy in cubic zinc blende structure and the angles between two different 111 planes are 70.5° or 109.5°. Therefore, the change of growth direction is inclined to be <111> and the bending angle is mostly close to 70.5° or 109.5°. However, due to their difference in the bending degree, the densities of SFs in local areas for approximately 70° and 110° kinks are different. When the bending angle is approximately 70°, the curvature is so sharp and supposed to cost larger energy. As a result, the internal stress would be larger than that of approximately 110° kinks, which needs massive and dense SFs to release. In addition, the sharp curvature makes the formation of approximately 70° kinks more difficult, which can be interpreted by presence of a smaller percentage with approximately 70° kink than that of approximately 110° kink as illustrated in Figure 1d.

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