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I'm trying to get a set of FTIR or (FTIR like range) x/y numerical data points for a couple of elements, namely Silver, Platinum, Palladium, Gold and Sodium. I've looked on line and found images only of the FTIR but I need the numerical x/y data points with the largest wavelength range. I tried NIST but they just show the NMR data. Is there a site where I can get just these or can someone send these/post these for me? And is it possible to get an FTIR of Sodium just by itself or does it need to be combined with another element.

Thanks

Please note I know metals (due to covalent bonds) don't work well with FTIR but I'm trying to get / see if it's possible to get a large wavelength range analysis of the items above like in FTIR. Sorry for using the FTIR term I don't know the proper term to use at the moment.

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I don't know about the IR spectra of metals. Certainly metals will have vibrational spectra, but I'm sure where to find it (if NIST does not have).

I can tell you how to get x/y data from NIST, if they have the spectrum.

For example, for benzoic acid. At the bottom of the page, there is a link to download the sepctrum in JCAMP-DX format. The .JDX file format is really a space-delimited text file containing x/y data with some markup at the front for the JCAMP plugin.

JCAMP-DX file in Notepad - save as .TXT

See all that lovely x/y data? Force the .JDX file open in your favorite text editor, like notepad. Do not use a word processor - they will add additional markup. Do not use a spreadsheet program yet. Spreadsheets can open .JDX files, but they won't always choose the most helpful delineation. Once open in notebook, resave the file as a text (ascii) file. Make sure you type in the .txt to change the extension (alternately, you can just change the extension to .txt using any other means you may feel comfortable with).

Now... open your favorite spreadsheet program, and use it to open your shiny new text file. You may have to tell the program to look for "all files" (MS Excel is bad about this). You should get some dialog/options on how to open the file. Choose "Delimited" if its an option, and when it comes time to choose your delimiters, make sure your choice includes "space":

Choosing the space delimiter in MS Excel

Now you should have a file with the x/y data. The first column is wavenumber (at least for IR) and the second is transmission ($\frac{I_{\text{out}}}{I_{\text{in}}}$). Some of these files have more than one column of y-data. When I graphed each column from the benzoic acid file, I got the same spectrum (almost).

x/y data and IR spectrum in Excel

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The absorption spectrum of any material is related to the dielectric constant/refractive index. Since there are no sharp resonance peaks for metals in the infrared, the absorption spectrum is pretty boring. However, there are many sources of data for metals. The most comprehensive set of data is the Handbook of Optical Constants of Solids by Edward D. Palik. It is a four volume set that should be available in most university libraries. The numbers for the most common metals can be downloaded in csv form from http://refractiveindex.info/.

With the refractive index in hand, the imaginary part of the index can be related to the extinction coefficient as $\alpha=\frac{\omega}{c}k$ where $\omega$ is the angular frequency of light, $c$ is the speed of light, and k is the imaginary part of the index.

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I don't know where you can get the X/Y data, but you can try to digitize the images you have found using something like a plot digitizer. I know it's not the best solution, but in bad circumstances it can work.

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For most of the metals have a look at Optical properties of the metals Al, Co, Cu, Au, Fe, Pb, Ni, Pd, Pt, Ag, Ti, and W in the infrared and far infrared Applied Optics, Vol. 22, Issue 7, pp. 1099-1119 (1983). You will find something like this:

enter image description here

OCR software could help you to retrieve the data.You can use $k$ as an index that indicates the amount of absorption loss. Free pdf of another version here.

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