# 5.5. Special plots for XAS data¶

## 5.5.1. Special plots for the current group¶

**Quad plot**The quad plot is the default plot that gets made when data are first imported. Using the current set of processing parameters, the data are displayed in energy, k, R, and back-transform k all in the same plot window. This plot can also be made by right-clicking on the

`kq`button.**Normalized data and derivative**This plot type shows the normalized μ(E) spectrum along with its derivative. The derivative spectrum is scaled by an amount that makes it display nicely along with the normalized data.

**Data + I0 + signal**I

_{0}can be plotted along with μ(E) and the signal as shown below. The I_{0}and signal channel is among the data saved in a project file. This example shows μ(E) of Au chloride along with the signal and I_{0}channels. This plot can also be made by right-clicking on the`E`button. (The norm+deriv plot can be configured for right-click use with the ♦Athena→right_single_e configuration parameter.)**k123 plot**A k123 plot is a way of visualizing the effect of k-weighting on the χ(k) spectrum. The k

^{1}-weighted spectrum is scaled up to be about the same size as the k^{2}-weighted spectrum. Similarly, the k^{3}-weighted spectrum is scaled down. This plot can also be made by right-clicking on the`k`button.**R123 plot**A R123 plot is a way of visualizing the effect of k-weighting on the χ(R) spectrum. The Fourier transform is made with k-weightings of 1, 2, and, 3. The FT of the k

^{1}-weighted spectrum is scaled up to be about the same size as the FT or the k^{2}-weighted spectrum. Similarly, the FT of the k^{3}-weighted spectrum is scaled down. The current setting in the R tab is used to make this plot. For this figure, the magnitude setting was selected. This plot can also be made by right-clicking on the`R`button.

## 5.5.2. Special plots for the marked groups¶

The marked.

submenu offers two special kinds of plots relating to the set of groups in the group list that have been**Bi-Quad plot**This special plot is like the quad plot described above, but is used to compare two marked groups. To make this plot you must have two – and only two – groups selected from the group list. This plot can also be made by right-clicking on the

`q`button.**Plot with E0 at 0**This special plot is used to visualize μ(E) spectra measured at different edges. Each spectrum, Cu and Fe in this example, is shifted so that its point of E

_{0}is displayed at 0 on the energy axis.**Plot I0 of marked groups**This plot allows examination of the I

_{0}signals of a set of marked groups. This plot can also be made by right-clicking on the`E`button. (The other two special marked groups plots can be configured for right-click use with the ♦Athena→right_marked_e configuration parameter.)**Plot scaled by edge step**The marked groups can be plotted as normalized μ(E), but scaled by the size of the edge step. Without flattening, this is identical to plotting the μ(E) data with the pre-edge line subtracted. Otherwise, it is different in that the post-edge region will be flattened and will oscillate around the level of the edge step size.

## 5.5.3. Special plots for merged groups¶

When data are merged, the standard deviation spectrum is also computed and saved in project files. The merged data can be plotted along with its standard deviation as shown in the merge section (Figure Fig. 9.7) in a couple of interesting ways.

**Merge + standard deviation**In this plot, the merged data are displayed along with the standard deviation. The standard deviation has been added to and subtracted from the merged data. This is the plot that is displayed by default when a merge is made. This behavior is controled by the ♦Athena→merge_plot configuration parameter.

**Merge + variance**In this plot, the standard deviation spectrum is plotted directly. It is scaled to plot nicely with the merged data. The point of this plot is to see how the variability in the data included in the merge is distributed in energy.

## 5.5.4. Phase corrected plots¶

When the phase correction check button is clicked on, the Fourier transform for that data group will be made by subtracting the central atom phase shift. This is an incomplete phase correction – in ATHENA we know the central atom but do not necessarily have any knowledge about the scattering atom.

Note that, when making a phase corrected plot, the window function in R is not corrected in any way, thus the window will not line up with the central atom phase corrected χ(R).

Also note that the phase correction propagates through to χ(q). While the window function will display sensibly with the central
atom phase corrected χ(q), a `kq` plot will be
somewhat less insightful because phase correction is not performed on
the original χ(k) data.

## 5.5.5. XKCD-style plots¶

ATHENA can make plots in a style that resembles the famous XKCD comic.

To make use of this most essential feature, you should first download and install the Humor-Sans font onto your computer.

Once you have installed the font, simply check

. Enjoy!DEMETER is copyright © 2009-2016 Bruce Ravel – This document is copyright © 2016 Bruce Ravel

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