Tecnai on-line help manual -- Options - UT Southwestern

<strong>Tecnai</strong> on-line help Options 92Options Software version 27.4.5 Diffraction patternThe spot diffraction pattern can be displayed with the zone axis shown at the center. Note that a cameraconstant larger than 10 is necessary to display a pattern (when the spots are too close together andoverlap they disappear). The spot pattern can be quite sensitive to small deviations of the crystal fromthe zone axis (in order to set the crystal exactly to the zone axis, the Tilt to function can be used). Thedisplay of the labels of the spot indices can be suppressed by removing the check from the DiffractionDisplay check box.Please note: The diffraction pattern displayed is based on the crystallographic parameters as input. Thismay deviate from the true diffraction pattern as seen on the microscope because the k-Space Controlsoftware does not account for structure factors, multiple scattering and possible forbidden diffractions.7.4.6 LatticeThe display can be set so that a projection of the crystal unit cell is shown. In the center, the unit cell isoutlined and circles display the generalized positions in the unit cell (so at the corners for Primitive,corners and faces for Face-centered, etc.). For unit cells beyond the central one (their number dependson the setting of the Lattice points on the Display tab of the Control Panel flap-out) only the circles areshown and no further lines.A lattice display with a value of 1 selectedfor an all-face centered cubic structure in orientation.