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Buying a Used FT-IR Spectrometer

Close up of FT-IR diamond ATR

Why should you consider buying a second-hand FT-IR instrument?

What is FT-IR spectrometry used for?

FT-IR spectrometry is used to qualitatively analyse a wide range of materials such as polymers, pharmaceuticals, solvents, paints, adhesives, and more. All molecules have bonds between atoms, which have specific vibrational and rotational energies which, conveniently for us, correspond with electromagnetic radiation in the infrared range. When infrared radiation is directed at the sample, some wavelengths are absorbed by those bonds. Using specialist software and spectrum libraries it is exceptionally quick and easy to identify a very wide range of materials based on the wavelengths at which they absorb.

Perking Elmer is10 FT-IR instrument with laptop
At Richmond Scientific, we stock a range of FT-IR spectrometers to suit all budgets

Why buy a second-hand FT-IR instrument?

FT-IR spectrometers can be very expensive to buy new. The main driver for most people buying a second-hand instrument is price. FT-IR spectrometers rarely need parts replacing or fixing, so they remain effective for a very long time. It is often possible to buy a high-quality functional used FT-IR for a fraction of the price of new.

Beyond price, there is the environmental aspect. It is obviously far better for the planet to keep equipment in circulation for as long as possible, rather then manufacturing new equipment and condemning perfectly good kit to landfill. Our dedicated Richmond Scientific FT-IR engineers are on hand to ensure all FT-IRs that come through our doors are in top condition before being offered out to customers at a great price.

Parts of an FTIR Spectrometer

One of the reasons FT-IR spectrometers are so robust and long-lasting is that they have no moving parts, and very few parts that need replacing. Despite being an exceptionally valuable analytical tool, FT-IR spectrometers are relatively simple instruments, with a small number of parts the user (or person maintaining the equipment) needs to be aware of.

FT-IT back panel with desiccant trays and screwdriver
Desiccant helps to keep the instrument free of moisture to extend the lifetime of the components and ensure optimum results

IR Sources

FT-IR spectrometers need to generate infrared radiation of known wavelength in the mid-to-near IR range. This is done by heating a source (typically silicon carbide or tungsten) to a very high temperature. This emits IR radiation, which can be measured by the detector. IR sources do eventually wear out (think of them like a fancy lightbulb) and can be replaced easily.

Beam Splitters

The clue’s in the name for this one. The beam splitter (you guessed it) splits the IR beam, directing 50% to be transmitted through the sample, and reflecting 50% for comparison. Beam splitters are often KBr or Quartz, and can be changed if needed based on the wavelength range required.

ATR Accessories

Various types of ATR exist for different types of sample. ATRs are used to hold the sample during measurement, and have different materials and configurations depending on the sample. For polymer analysis, where the sample can be made into a film, an ATR may not be needed, as the beam can be passed straight through the sample. ATRs are made with various crystals, designed for maximum contact and optimal penetration of the sample.


Detectors measure the intensity of the infrared radiation that hits them, and converts it to a signal which can be analysed and interpreted by the user.

FT-IR technical support

At Richmond Scientific we have in-house expert engineers who service and test all the instruments that we sell. If you need advice on which FT-IR instrument you require, or if you have equipment that you would like servicing or inspecting, please call our team on 01257 270433.

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