It is the branch of spectroscopy that includes the production, study, and use of emission, absorption, and reflection spectra in the infrared region of the spectrum.
FT-IR stands for Fourier Transform InfraRed, the preferred method of infrared spectroscopy. In. infrared spectroscopy, IR radiation is passed through a sample. Some of the infrared radiation is. absorbed by the sample and. some of it is passed through. (transmitted). The resulting. spectrum represents the molecular. absorption and transmission, creating a molecular ﬁngerprint. of the sample. Ininfrared spectroscopy, IR radiation is passed through a sample. Some of the infrared radiation isabsorbed by the sample andsome of it is passed through(transmitted). The resultingspectrum represents the molecularabsorption and transmission,creating a molecular ﬁngerprint No two organic compounds have the same infrared spectrum and so individual, pure compounds can be identified by examination of their spectra. In the region, 7 - 11 microns (1430-910 cm -1) there are many absorption bands and even pairs of almost identical organic molecules show up differences here.  Definition of Near-infrared spectroscopy (NIR). Search the Dictionary. NIR spectroscopy is the measurement of the wavelength and intensity of the absorption of near-infrared light by a sample. Near-infrared light spans the 800 nm - 2.5 µm (12,500 - 4000 cm-1) range and is energetic enough to excite overtones and combinations of molecular vibrations to higher energy levels Infrared Spectroscopy. (also IR spectroscopy), the branch of spectroscopy that includes the production, study, and use of emission, absorption, and reflection spectra in the infrared region of the spectrum. Infrared spectroscopy is used in the study of the structure of semiconductors, polymers, biological entities, and living cells. High-speed spectrometers make it possible to obtain absorption spectra in fractions of a second and are used in the study of rapidly transpiring chemical reactions. The portion of the infrared region most useful for analysis of organic compounds is not immediately adjacent to the visible spectrum, but is that having a wavelength range from 2,500 to 16,000 nm, with a corresponding frequency range from 1.9*10 13 to 1.2*10 14 Hz. 1. Introduction. As noted in a previous chapter, the light our eyes see is but a small part of a broad spectrum of electromagnetic radiation. On the immediate high energy side of the visible spectrum lies the ultraviolet, and on the low energy side is the infrared. Infrared (IR) absorption spectroscopy is the measurement of the wavelength and intensity of the absorption of mid-infrared light by a sample. Mid-infrared light (2.5 - 50 µm, 4000 - 200 cm-1) is energetic enough to excite molecular vibrations to higher energy levels. IR spectroscopy is used to confirm the identify of a particular compound and as a tool to help determine the structure of a newly synthesized molecule (with NMR spectroscopy and mass spectrometry). Mechanism of IR absorption. dipole moment operator: µ = µo + (r-re)(dµ/dr) + ... higher terms. infrared spectroscopy (inˑ·fr ·redˈ spek·tr sˑ·k ·pē) , n an instrumental technique used to identify substances—in particular the functional groups present in organic compounds by measuring their absorption of infrared radiation over a range of frequencies.  Definition of SPECTROSCOPY. 1. : the process or technique of using a spectroscope or spectrometer. 2. : the production and investigation of spectra. ADVERTISEMENT.  IR. 1. Of or relating to electromagnetic radiation between microwaves and red visible light in the electromagnetic spectrum, having frequencies between 300 gigahertz and 400 terahertz and wavelengths between 1 millimeter and 750 nanometers. 2. Generating, using, or sensitive to infrared radiation. Definition of Infrared Spectroscopy. Infrared spectroscopy (IR) is a characterization tool chemists use to help determine the molecular structure. IR capitalizes on the concept that functional groups absorb specific frequencies of energy based on their structure. When a functional group absorbs energy, it can vibrate in a bending or stretching mode and the characteristic energy for this vibrational mode is reported in wavenumbers.
http://mmrc.caltech.edu/FTIR/FTIRintro.pdf http://www.rsc.org/learn-chemistry/collections/spectroscopy/introduction http://www.chemicool.com/definition/near_infrared_spectroscopy_nir.html http://encyclopedia2.thefreedictionary.com/Infrared+spectroscopy https://www2.chemistry.msu.edu/faculty/reusch/VirtTxtJml/Spectrpy/InfraRed/infrared.htm http://www.chemicool.com/definition/infrared_absorption_spectroscopy_ir.html http://medical-dictionary.thefreedictionary.com/infrared+spectroscopy http://www.merriam-webster.com/dictionary/spectroscopy http://www.thefreedictionary.com/Near+infrared http://www.chegg.com/homework-help/definitions/infrared-spectroscopy-6
infrared spectroscopy definition