Agilent Cary 630 FTIR Spectrometer Supports Undergraduate Teaching Laboratories

Significance of the Topic

This summary highlights the role of FTIR spectroscopy in undergraduate teaching laboratories. Fourier-transform infrared spectroscopy is essential for qualitative and quantitative chemical analysis. In multiuser academic settings, instruments must be user-friendly, rugged, compact, and affordable. The Agilent Cary 630 FTIR meets these demands, enabling students to gain hands-on experience in organic, analytical, and physical chemistry experiments.

Objectives and Study Overview

This application study demonstrates how the Cary 630 FTIR spectrometer can be employed in a standard undergraduate physical chemistry experiment. The primary goal is to measure the rotational–vibrational spectrum of hydrogen chloride gas and extract molecular parameters such as rotational constants and bond length, illustrating both theoretical concepts and practical analytical skills.

Instrumentation

• Agilent Cary 630 FTIR spectrometer with compact, sealed optics and permanently aligned interferometer.
• Transmission accessory (G8043 #300) coupled with a 50 mm gas cell (G8043 #306).
• Agilent MicroLab Expert software (G4097AA) for instrument control, data acquisition, and spectral analysis.

Methodology

Prior to sample analysis, a background spectrum was acquired with the empty gas cell. The HCl sample was introduced into the cell, and spectra were recorded at 2 cm⁻¹ resolution with an optical gain set to yield a signal intensity of 18 000–25 000. Sixty-four scans were collected using boxcar apodization and a zero-fill factor of two to enhance peak shape and resolution. Parameter variations such as scan number, apodization, and zero‐filling can be explored to demonstrate their influence on spectral quality.

Main Results and Discussion

The recorded absorbance spectrum displays well-resolved P- and R-branch lines around the fundamental vibrational band of HCl. Ten individual rotational transitions in each branch were identified. Analysis of line positions allows calculation of rotational constants and estimation of the HCl bond length under the rigid‐rotor approximation, reinforcing theoretical models of diatomic molecules.

Benefits and Practical Applications

• Rapid data acquisition with minimal training, supporting high-throughput teaching labs.
• Versatile sampling interfaces (gas, liquid, solid, ATR, diffuse reflectance) facilitate diverse experiments.
• Rugged, portable design suitable for shared bench spaces or fume hoods.
• Integrated software tools for spectral manipulation, library searching, and both univariate and multivariate quantitative analysis.

Future Trends and Applications

Emerging developments include enhanced chemometric algorithms for complex mixture analysis, integration with remote-learning platforms, expanded spectral libraries with AI-assisted interpretation, and the development of portable FTIR systems for field-based instruction. Such trends will further streamline teaching workflows and broaden the scope of instructional experiments.

Conclusion

The Agilent Cary 630 FTIR spectrometer combines ease-of-use, robust optics, and flexible sampling in a compact footprint, making it an ideal choice for undergraduate analytical and physical chemistry laboratories. The successful measurement of HCl’s rotational spectrum illustrates its capability to connect theoretical concepts with practical laboratory skills.

References

• Numerous laboratory experiments can be found through simple internet searches. These resources detail sample handling, safety precautions, theoretical background, and calculation procedures based on collected FTIR data.
• Garland, Nibler, Shoemaker. Experiments in Physical Chemistry, 8th Edition (2008).