Page 15 - Shimadzu AIRsight
P. 15

AIRsight


 Infrared Spectroscopy and
 Raman Spectroscopy












 Differences between Infrared Spectroscopy and
 Raman Spectroscopy
               Applicable components:                        Applicable components:
               Plastics, organic food components, and some inorganic   Carbon materials (CNT, DLC, diamond, etc.), pigments,
               components                                    additives and other inorganic substances, and some organic
 Infrared Spectroscopy  Raman Spectroscopy                   substances


 Samples are irradiated with infrared   Samples are irradiated with laser   Features  Features
 light to measure how much light is   light to measure the amount of
 transmitted through the sample and   Raman scattering that occurs   • Extensive spectral libraries available  • Especially well-suited for analyzing carbon materials
 how much is reflected.  from the sample.                        (carbon nanotubes, diamond, etc.)
                 • Widely used, resulting in plentiful application
                   examples                                     • Enables analysis in the depth direction
                 • Rarely damages samples
                                                                • Transparent materials (glass, etc.) do not absorb
                 • ATR (optional), transmission, or reflection methods   visible laser light, so samples can be measured
 Molecules are identified based on   can be selected depending on the sample  directly in containers
 the difference between the
 wavelength of the irradiated laser                             • High spatial resolution (extremely small areas can be
 light and the wavelength of the                                 targeted)
 Raman scattered light (Raman shift).
 Molecules are identified based on
 the wavelength (or wavenumber) of
 absorbed infrared light.

 Ground state
               Examples of Problems Solved




                     Contaminant components cannot be              Measuring the same sample location with
                     identified with an infrared microscope alone.  both infrared and Raman is desired.
 Enables Acquisition of Mutually
 Complementary Molecular Information

                                                                   The infrared and Raman microscope enabled
 Infrared and Raman Spectra of Polyester   Polar bonds  Non-polar bonds  Contaminant was identified based on both   the same location to be quickly measured
 (Laser Wavelength: 532 nm)  O-H, N-H, C=O, C-O-C  C=C, S-S, C-S  infrared and Raman measurement results.  without moving the sample.



 C=O  C=C  – Infrared spectrum
 C-O-C
 – Raman spectrum    The target area is too small to be measured   Detailed analysis of both organic and
 C-O-C               with an infrared microscope.                  inorganic components is desired.



                                                                   Combining infrared and Raman spectroscopy
                     The infrared and Raman microscope enabled     enabled material analysis.
                     even smaller areas to be targeted and
 1750  1500  1250  1000  750  measured.
 cm -1


 14                                                                                                               15
   10   11   12   13   14   15   16