Infrared IR spectroscopy is a powerful analytical technique used to identify functional groups in organic compounds by analyzing the vibrations of molecular bonds. Here is a step-by-step procedure for the analysis of functional groups in a compound using IR spectroscopy:1. Sample preparation: Prepare a thin film of the compound by dissolving it in a suitable solvent and placing a drop of the solution between two IR-transparent windows such as potassium bromide or sodium chloride plates . Alternatively, you can mix the compound with an IR-transparent solid like potassium bromide and press it into a thin pellet.2. Record the IR spectrum: Place the sample in the IR spectrometer and record the spectrum over a range of wavelengths typically 4000-400 cm-1 . The instrument will measure the absorption of infrared radiation by the sample at different frequencies, producing a plot of absorbance or transmittance versus wavenumber cm-1 .3. Identify characteristic peaks: Examine the recorded IR spectrum and identify the characteristic peaks corresponding to specific bond vibrations. These peaks appear at specific wavenumbers and can be used to identify the presence of functional groups in the compound.4. Consult a reference table: Use a reference table of IR absorption frequencies for common functional groups to help identify the peaks in your spectrum. These tables provide the characteristic wavenumbers for various bond vibrations, such as C-H, C=O, C-N, and O-H, among others.5. Analyze the fingerprint region: The fingerprint region below 1500 cm-1 contains many overlapping peaks that are unique to each compound. While it may be difficult to assign specific functional groups to these peaks, comparing the fingerprint region of your compound to that of known compounds can help confirm the presence of certain functional groups or identify the compound itself.6. Confirm the functional groups: Once you have identified the possible functional groups based on the characteristic peaks in the IR spectrum, you can confirm their presence by comparing your spectrum to reference spectra of known compounds containing those functional groups. This will help you verify your assignments and ensure the accuracy of your analysis.7. Interpret the results: Based on the identified peaks and confirmed functional groups, you can now determine the structure of the compound or at least gain valuable information about its composition. This information can be used in conjunction with other analytical techniques, such as nuclear magnetic resonance NMR spectroscopy or mass spectrometry, to fully elucidate the structure of the compound.