HATR Product Description:

Horizontal Attenuated Total Reflectance (HATR) accessories successfully replace constant path transmission cells, salt plates and KBr pellets used in the analysis of liquid, semi-liquid materials and solids. HATRs feature a constant and reproducible effective pathlength and are well suited for both qualitative and quantitative applications. The HATR may be configured with flat or trough plates, and for up to 20 internal reflections. Flow cells and heating options are also available.

Excellent energy throughput offering high signal-to-noise ratio

Up to 20 internal reflections for maximum sensitivity for low concentration components

HATR plates with ZnSe, KRS-5, Ge, AMTIR, and Si crystals

Temperature control options available upon request.

A Beginner’s Guide to the Technique of Horizontal ATR

Horizontal Attenuated Total Reflectance (ATR) is a configuration of the ATR spectroscopy technique where the incident infrared (IR) beam is directed horizontally onto the sample, creating an interface with the ATR crystal or prism. In this setup, the ATR crystal or prism is oriented horizontally, and the sample is placed on top of it, making contact with the crystal's surface.

Key features and considerations of Horizontal ATR include:

1. Sample Placement: The sample is placed horizontally on the ATR crystal or prism, creating an intimate contact with the crystal's surface. This configuration allows for efficient transmission of the IR beam into the sample, promoting good signal intensity.

2. Geometric Reflection: In Horizontal ATR, the incident IR beam undergoes internal reflection at the interface between the ATR crystal and the sample. The reflected beam is then detected by the spectrometer.

3. Surface Sensitivity: Like other ATR configurations, Horizontal ATR is surface-sensitive, primarily probing the topmost layers of the sample. It is especially useful for analyzing thin films, coatings, and surface contaminants.

4. Sampling Depth: The penetration depth of the IR beam in Horizontal ATR is limited to the near-surface layers of the sample, making it ideal for examining surface properties and adsorbed species.

5. Application Flexibility: Horizontal ATR can be used for a wide range of sample types, including liquids, gels, soft solids, and powders. It is particularly valuable when dealing with samples that are difficult to prepare or handle for traditional transmission measurements.

6. Minimal Sample Preparation: One of the advantages of Horizontal ATR is its minimal sample preparation requirements. Since the sample is simply placed in contact with the ATR crystal, there is no need for elaborate sample preparation techniques.

7. Rapid Analysis: Horizontal ATR typically allows for fast data acquisition, making it suitable for high-throughput analysis and screening applications.

8. Experimental Setup: The experimental setup for Horizontal ATR is relatively straightforward and easy to use, making it accessible to both novice and experienced spectroscopists.

Horizontal ATR is commonly used in various fields, such as materials science, pharmaceuticals, forensic analysis, and quality control. It offers valuable information about surface composition, molecular interactions, and surface adsorption phenomena.

However, it is essential to consider the limitations of Horizontal ATR, such as the shallow penetration depth, which may not be suitable for bulk sample analysis. Additionally, the signal intensity and sensitivity can be affected by the refractive indices of the ATR crystal and the sample.

The choice between Horizontal ATR and other ATR configurations (such as Vertical ATR or Single Reflection ATR) depends on the specific sample, research objectives, and the required sensitivity and depth of analysis. Researchers often select the ATR setup that best suits their needs to achieve accurate and informative spectroscopic results.