How do you prepare a sample for infrared spectroscopy?

1) Making a sandwich To prepare a liquid sample to IR analysis, firstly place a drop of the liquid on the face of a highly polished salt plate (such as NaCl, AgCl or KBr), then place a second plate on top of the first plate so as to spread the liquid in a thin layer between the plates, and clamps the plates together.

How does IR ATR work?

How does it work? An ATR accessory operates by measuring the changes that occur in an internally reflected IR beam when the beam comes into contact with a sample. An IR beam is directed onto an optically dense crystal with a high refractive index at a certain angle.

How do you prepare samples for FTIR analysis?

Add about 1 to 2 % of your sample, mix and grind to a fine powder. For very hard samples, add the sample first, grind, add KBr and then grind again. The sample must be very finely ground as in the Nujol mulling technique to reduce scattering losses and absorption band distortions.

Why do we use ATR in FTIR spectroscopy?

Attenuated Total Reflectance (ATR) is a sampling method that introduces light onto a sample in order to acquire structural and compositional information. ATR is one of the most used sampling technologies for FTIR Spectroscopy. The reason for the ubiquitous use of ATR is that it enables solids and liquid samples to be analyzed neat – simplifying

What do you need to know about the ATR technique?

Introduction to ATR technique (Attenuated Total Reflectance) While traditional IR spectrometers have been used to analyze solids, liquids and gases by means of transmitting the infrared beam directly through the sample, ATR uses the reflectance of the sample instead.

What is the ATR protocol in JASCO FTIR-4100?

ATR protocol (JASCO FTIR-4100) 1. Introduction to ATR technique (Attenuated Total Reflectance) While traditional IR spectrometers have been used to analyze solids, liquids and gases by means of transmitting the infrared beam directly through the sample, ATR uses the reflectance of the sample instead.

How to prepare a sample for near infrared analysis?

For near‐ infrared analysis, CsI or KBr can be selected. You can prepare a KBr Pellet as follows: (a) The powder sample and KBr must be ground to reduce the particle size to less than 5 mm in diameter. Otherwise, large particles scatter the infrared beam and cause a slope baseline of spectrum.