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Acquiring an IR Spectrum

The organic chemistry teaching labs at CU Boulder have 4 Nicolet FT-IR instruments: an Avatar 320, an Avatar 370, and two IR 200s. There is one in the instrument room attached to each of the lab rooms. If the instrument in your lab has a long line, you can also use the one in M1B70.

Avatar 320 - Located in M1B25. Avatar 370 - Located in M1B70. IR 200 - Located in M1B27 and M1B73.

Acquiring a Spectrum

First, prepare your sample as directed in the liquid sampling technique or solid sampling technique pages. Most likely, the EZOMNIC program has already been launched, a background run, and is ready to go - in this case, you can skip to the sample collection step. If not, double-click the icon for the program.
Run a background. First, make sure there are no plates in the IR, then click on the Col Bkg icon in the upper tool bar.
Wait for the instrument to run four background scans. This is necessary because it provides a baseline that the instrument will subtract out of subsequent scans - it's a way to compensate for the presence of water, CO2, impurities in salt plates, etc.
If you have scanned the background properly, this is what it looks like. If it does not look like this, for instance, if it has a lot more bands, you probably left IR plates in the instrument when you took the background.
Place the salt plate(s) in the instrument. Click on the icon in the upper toolbar that says "Col Smp" to collect the sample.
Your spectrum should appear after a few seconds.
If it looks like this, for instance, if it is a straight or jaggedy line, someone probably left a sample in the instrument when the background was run. You'll need to collect a fresh background.
If you are happy with your spectrum, you can print to the default printer for your lab.

Back to IR Spectroscopy