Home
To Precipitate

To Precipite allows to model a precipitate embeded in a matrix. As an example a Y2O3 precipitate will be embeded in an iron matrix of orientation [001].

The first steps consist in transforming the precipitate crystal stuctures to make it orthogonal in a [111] projection. It is necessary to define orthogonal matrix/precipitate in order to cut the model into slices. The Y2O3 crystal file is first loaded and using Make orthogonal menu item of menu Crystal (Figures 1, 1).

The toolbar contains tool buttons to:

Figure1

Figure 1 Y2O3 [111] view.

Figure2

Figure 2 Y2O3 orthogonal cell.

ToPrecipitate first duplicate the Y2O3 crystal

Figure3

Figure 3 ToPrecipitate window to duplicate the Y2O3 orthogonal cell.

Figure3a

Figure 3a ToPrecipitate window to duplicate the Y2O3 orthogonal cell.

Figure3b

Figure 3b ToPrecipitate window to duplicate Fe matrix.

Figure3c

Figure 3b Model of the Fe matrix.

Figure3d

Figure 3d Model of the Fe matrix.

Figure3e

Figure 3e Atoms list of Y2O3 precipitae in Fe matrix.

Figure3f

Figure 3f Model Y2O3 in Fe.

Figure4a Figure4b

Figure 4a SAED.

Figure 4a Projected potential.

Figure4c Figure4d

Figure 4c HAADF.

Figure 4d WPOA.

Figure5

Figure 5 Model Y2O3 in Fe cut in 17 slices 0f 0.2 nm thick.

Figure6

Figure 6 Slice 6 of Y2O3 in Fe.

Figure7

Figure 7 Load the first slice.

Figure8

Figure 8 Open the multislicer with Super-cell and load all slices (++).

Adjust the imaging conditions and set the size of the defocused images series (Figures 9a, 9b).

Figure9a Figure9b

Figure 9a Illumination.

Figure 9a Defocus series size.

Figure10a
  • Amorphous layer at model's top and bottom.
  • Show atomic columns.
  • Save images.
  • Show images after each slice.
  • Save wave-functions.
  • Plot reflections.

Figure 10a Iteration options.

Selected options.

Finally start the calculation. When the calculation stops images are displayed. Figure 11 shows a defocus series image at after the last slice.

Figure11

Figure 11 Defocus series of Y2O3 in Fe.

Images at different ThicknessMeasurement can be displayed selecting the Plot image panel (Fig. 12). The effect of defocus and several optical Aberrations can be introduced (Figures 13a, 13b, 13c, 13d).

Figure12

Figure 12 Images at different thickness can be displayed selecting the Plot image panel.

Figure13a Figure13b

Figure 13a Thickness change.

Figure 13b Defocus change.

Figure13c Figure13d

Figure 13c Coma.

Figure 13d 3-Fold astigmtism.

In order to simulate the effect of Aberrations from W00 up to W88 (wavefront deformation), use the HRTEM imager (Fig. 14).

Figure14

Figure 14 HRTEM imager loaded with the a wave-function calculated with Y2O3 in Fe model. 300 μm C34 or A3 or W44 of 4-Fold astigmatism introduced.

Efects of tilted illumination (Figures 15a, 15b), objective aperture centering (Figures 16a, 16b) or magnification can be simulated (Figures 17a, 17b, 17c, 17d).

    Figure15a Figure15b

    Figure 15a Tilted illumination.

    Figure 15b HRTEM image.

    Figure16a Figure16b

    Figure 16a Displaced objective aperture.

    Figure 16b HRTEM image.

    Figure17a Figure17b

    Figure 17a High magnification.

    Figure 17b High contrast HRTEM image.

    Figure17c Figure17d

    Figure 17c Low magnification.

    Figure 17d Low contrast HRTEM image.