Quantitative Applications:

You have learnt in which how UV-VIS spectrometry could be used for quantitative determinations.  Within case of IR spectrometry the quantitative use is subject to a number of practical and instrumental problems. A few of these are as follows:

• Narrowness of the IR bands
• Low intensity of the source and low sensitivity of the transducer
• Non availability of the matched cells for the sample and reference
• Interference by solvents and IR absorbing air contaminants

In the light of these factors the quantitative  application of IR needs  a thorough planning  of the  experiment  and a skilled  execution  of the procedure to obtain the spectrum. Therefore in case of FT-IR, the results are much better.  Further, the method of concurrent determination could also be used for quantitative analysis using IR spectrometry.

A number of easy, portable and yet dependable IR spectrometers are available which might be used to quantitatively analyse a mixture of gaseous pollutants in a short time. These instruments are IR filter photometers and provide good results but not as good as are probable along with UV-VIS spectrophotometers.