The structure of potassium hexatitanate (K_2Ti_6O_13) nanowires has been investigated using both the Rietveld powder diffraction profile fitting technique and high resolution transmission electron microscopy (HRTEM) i...The structure of potassium hexatitanate (K_2Ti_6O_13) nanowires has been investigated using both the Rietveld powder diffraction profile fitting technique and high resolution transmission electron microscopy (HRTEM) image simulations. From the Rietveld analysis it was shown that the nanowires had a monoclinic structure of the space group C2/M and the lattice parameters were a=1.5582 nm, 6=0.382 nm, c=0.9112 nm. HRTEM conclusions agree with refinement results obtained from experimental XRD data. The good agreement between the experimental and simulated images confirms that the nanowires is indeed K_2Ti_6O_13 nanowire.The growth axes of nanowires were mainly along the [010] direction.展开更多
The exit wave function including zero and high order Laue zones has been simulated by both multi-slice method and electron dynamic diffraction analytical expression. Coincidence of the simulations by these two methods...The exit wave function including zero and high order Laue zones has been simulated by both multi-slice method and electron dynamic diffraction analytical expression. Coincidence of the simulations by these two methods was achieved. The calculated results showed that the exit wave function highly dominated by zero order Laue zone, while high order ones modify the exit wave function to some extent depending on the situation. High order Laue zone effects become important for the following cases: sample consists of light elements, the thickness is very thin, lattice planar spacing perpendicular to the direction of the incident beam is large, and the electron beam has long wavelength. In these cases the exit wave function should be corrected by adding high order Laue zone effects. The analytical expression is effective and convenient for dealing with high order Laue zone effects.展开更多
基金This work was supported by the N ational Excellent Youth Foundation of China(Grant No.50025103)the National Natural Science Foundation of China(Grant No.20271037 and No.50171046)+1 种基金Major Project of National Natural Science Foundation of China(Grant No.90306014)Joint Project of NSFC and JSPS(No.50311140138).
文摘The structure of potassium hexatitanate (K_2Ti_6O_13) nanowires has been investigated using both the Rietveld powder diffraction profile fitting technique and high resolution transmission electron microscopy (HRTEM) image simulations. From the Rietveld analysis it was shown that the nanowires had a monoclinic structure of the space group C2/M and the lattice parameters were a=1.5582 nm, 6=0.382 nm, c=0.9112 nm. HRTEM conclusions agree with refinement results obtained from experimental XRD data. The good agreement between the experimental and simulated images confirms that the nanowires is indeed K_2Ti_6O_13 nanowire.The growth axes of nanowires were mainly along the [010] direction.
基金National Natural Science Foundation of China(No.10374077)the Key Foundation of Education Department of Hunan Province 01A003the Scientific Fund of Education Department of Hunan Province 03C187
文摘The exit wave function including zero and high order Laue zones has been simulated by both multi-slice method and electron dynamic diffraction analytical expression. Coincidence of the simulations by these two methods was achieved. The calculated results showed that the exit wave function highly dominated by zero order Laue zone, while high order ones modify the exit wave function to some extent depending on the situation. High order Laue zone effects become important for the following cases: sample consists of light elements, the thickness is very thin, lattice planar spacing perpendicular to the direction of the incident beam is large, and the electron beam has long wavelength. In these cases the exit wave function should be corrected by adding high order Laue zone effects. The analytical expression is effective and convenient for dealing with high order Laue zone effects.