Fourier Transform Infrared spectroscopy (FTIR) is one of the fundamental analytical techniques used in organic chemistry to help identify the structure and functional groups of unknown compounds. Most undergraduate organic laboratories have access to basic infrared spectrometers. In the Virtual ChemLab simulation, an FTIR spectrum can be measured on the solution contained in any flask or the separatory funnel after a reaction mixture has been worked up. The FTIR spectra that are shown in the simulation were scanned from the Aldrich FTIR library, and those that were not found in the Aldrich library were calculated based on spectra for similar structures.


An FTIR is measured by clicking on the FTIR machine and dragging the small salt plate to the solution of interest. The resulting FTIR spectrum will be displayed in its own window from 4500 to 400 wavenumbers. FTIR spectra of solutions containing mixtures are also allowed with the peaks adjusted for the relative concentrations. The OK button closes the FTIR window, and the Save button saves the FTIR to the lab book.


A spectra library containing over 700 spectra is available by clicking on the Spectra tab. When an FTIR spectrum is obtained from the library, the IUPAC and common name for the compound and several physical properties are listed in the text boxes above the spectra. Spectra from the library can also be saved to the lab book. When a spectrum is generated from the lab bench, the text boxes are left empty since the spectrum is an unknown. The IUPAC and common name text boxes can be used to write notes about the spectra that will be attached to the spectra if saved.