FTIR: Microscopy

FTIR: Microscopy
Simple FTIR spectrum contrasting raw measurement (blue) to reference (red) on HVAC sample

Fourier-transformed infrared spectroscopy (FTIR) is a nondestructive, optical technique used to analyze chemical composition and the optical properties of a material.

In an FTIR measurement, an initially wide range of infrared wavelengths are simultaneously shone upon an area of the sample. Using an interferometer, the FTIR system then extracts a specific wavelength band at a time and measures its light intensity: selectively detecting either reflected or transmitted beams. The operator will determine whether to target transmittance or reflectance intensity based on the sample’s composition and topography. After this initial measurement, the extracted wavelength band is subsequently scanned over the entirety of the wavelength range, capturing an intensity measurement at each band. The resulting values are then fourier-transformed to produce the initial sample spectrum. To isolate the real sample spectrum, a reference – or ‘blank’ – trial is conducted without any material inserted in the beam path. This spectrum is used to normalize the sample spectrum and to isolate the relevant specimen information from the total signal. In the wavelength range of interest, different types of chemical bonds absorb at different wavelengths: providing a spectral signature which is material dependent. The resulting background-subtracted spectrum can then be used to qualitatively identify chemical functional groups and trace chemicals present in the specimen.

ATR-FTIR is a variant FTIR measurement mode which uses a specialized crystal to generate multiple internal reflections along the lateral dimension of the sample, increasing signal-to-noise and surface sensitivity.

Base Pricing List
No item selected Add to Quote List
Techniques
Pricing Starts At
Action
+
FTIR: Microscopy
$250 / Sample

Strengths
  • Rapid results
  • Nondestructive analysis
  • Particularly well suited for organic chemical analysis
  • Robust reference libraries are available
Limitations
  • Requires reference or a standard / control sample to make positive chemical identifications
  • Most inorganic molecules do not exhibit an FTIR spectrum
Sample Requirements
  • Solid or liquid phase
  • Flat surface is ideal; other topographies are accepted, may impact data quality
  • Material must not be too reflective (e.g. high-reflection metallics), nor too transmissive (e.g. some glasses), for best results
Instruments Used for
Thermo Fisher Nicolet 6700 IR Spectrometer

Thermo Fisher Nicolet 6700 IR Spectrometer

  • 4 Analytical Modes / Measurement Accessories:
    1. Transmittance
    2. Specular Reflectance
    3. Attenuated Total Reflectance (ATR): both Ge and Diamond-C sampling systems
    4. NicPlan IR Microscope (transmittance and reflectance mapping with 20 µm spot size)

View Instrument Brochure

Example Outputs
<p>FTIR spectra from 3 plastic polymer materials – Polyethylene terephthalate (PET), Polyethylene (PE), Polypropylene (PP) – overlaid for comparison</p>

FTIR spectra from 3 plastic polymer materials – Polyethylene terephthalate (PET), Polyethylene (PE), Polypropylene (PP) – overlaid for comparison

<p>Simple FTIR spectrum contrasting raw measurement (blue) to reference (red) on HVAC sample</p>

Simple FTIR spectrum contrasting raw measurement (blue) to reference (red) on HVAC sample

Additional Resources

No resources available at this time.

Similar Techniques

no data found

No related techniques found.

comparison link sent successfully
please use valid email address
You need to have at least 2 techniques to compare
You can select maximum 5 techniques
Covalent uses cookies to improve your browsing experience and to help you access the most relevant information and services efficiently. To learn more, view our
Decline
I Accept Cookies
techniques selected
Select at least 2 techniques to compare Compare techniques