Figure 3: Transmission electron microscopy images and electron diffraction patterns of different cross-sections of individual Ag nanowires.

(a–c) Cross-section obtained by slicing a nanowire against the planes that have 45° with respect to the longitudinal axis of the nanowire. The inset in c presents a shadow image with the strongest contrast in the bottom subunit, indicating that the electron beam was well aligned against the low-index crystallographic axis of <010>. The electron diffraction (ED) pattern in c was recorded from the point #1 in b with an electron beam of ~10 nm in size. The reflection spots were indexed according to the difference of d-spacing along different crystallographic axes. The white circle whose centre overlaps the (000) reflection spot clearly shows that the (002) reflection spot is slightly farther than the (200) spot from the pattern centre, that is, the (000) spot. (d–g) Cross-section obtained by cutting a nanowire against the planes that are perpendicular to the longitudinal axis of the nanowire. The colours and Roman numerals in the parentheses correspond to the individual subunits labelled with the same colours and Roman numerals in d. The red arrow in g highlights the twin plane. The scale bars in b and d represent 20 and 10 nm, respectively. The scale bars in both f and g represent 5 nm.