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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).

Figure 1 Y2O3 [111] view.

Figure 2 Y2O3 orthogonal cell.
ToPrecipitate first duplicate the Y2O3 crystal

Figure 3 ToPrecipitate window to duplicate the Y2O3 orthogonal cell.

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

Figure 3b ToPrecipitate window to duplicate Fe matrix.

Figure 3b Model of the Fe matrix.

Figure 3d Model of the Fe matrix.

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

Figure 3f Model Y2O3 in Fe.
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Figure 4a SAED. |
Figure 4a Projected potential. |
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Figure 4c HAADF. |
Figure 4d WPOA. |

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

Figure 6 Slice 6 of Y2O3 in Fe.

Figure 7 Load the first slice.

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).
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Figure 9a Illumination. |
Figure 9a Defocus series size. |
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- Amorphous layer at model's top and bottom.
- Show atomic columns.
- Save images.
- Show images after each slice.
- Save wave-functions.
- Plot reflections.
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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.

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).

Figure 12 Images at different thickness can be displayed selecting the Plot
image panel.
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Figure 13a Thickness change. |
Figure 13b Defocus change. |
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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).

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).
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Figure 15a Tilted illumination. |
Figure 15b HRTEM image. |
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Figure 16a Displaced objective aperture. |
Figure 16b HRTEM image. |
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Figure 17a High magnification. |
Figure 17b High contrast HRTEM image. |
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Figure 17c Low magnification. |
Figure 17d Low contrast HRTEM image. |