IRSpektrum

IRSpektrum is the infrared spectrum of a material as measured by infrared spectroscopy. It provides a graphical representation of molecular vibrations and serves as a tool for identification, structural analysis, and quality control. The spectrum is typically plotted as absorbance or transmittance versus wavenumber (cm^-1), with the x-axis commonly covering the mid-infrared range from about 4000 to 400 cm^-1.

Measurement and data: Most IR spectra are obtained with Fourier-transform infrared (FTIR) spectrometers. Samples may be analyzed as thin films, pressed pellets with potassium bromide (KBr), or via attenuated total reflectance (ATR) without extensive preparation. The spectrum shows bands corresponding to stretching and bending motions of bonds such as O-H, C-H, N-H, C=O, and C-O. The region above approximately 2500 cm^-1 contains X-H stretches; the fingerprint region below ~1500 cm^-1 provides a unique pattern for identification.

Interpretation and limitations: Analysts compare IRSpektrum against reference libraries to identify components or confirm functional groups. Qualitative results are robust; quantitative work requires calibration and careful control of sampling geometry, path length, and baseline. Common limitations include overlapping bands, low signal intensity, and interference from moisture or carbon dioxide.

Applications: IRSpektrum is widely used in chemistry, polymer science, pharmaceuticals, material science, forensics, and environmental testing for identification, purity assessment, and monitoring of chemical reactions.

History: Infrared spectroscopy emerged in the early 20th century and matured with Fourier-transform techniques in the late 20th century, making IR spectra a routine analytical tool.