About Infrared Spectra Database of Mineral Species

FT-IR.ro project description & features

  • Interactive infrared spectra of common minerals; Users can zoom into the Raman spectrum, shift in any direction the wavenumber and the intensity axes, and if any part of the spectral display is clicked, that region will be highlighted and the specific wavenumber returned.

Last 5 entries of Infrared spectra

First use

Number of Infrared spectra: 6

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Introduction to FT-IR.ro project

Welcome to the FT-IR.ro project website containing an integrated database of Infrared spectra for minerals.

This database was undertaken to compensate other research studies about the infrared spectra of minerals.

The Infrared spectrometry completes very well the Raman spectrometry, in particular to demonstrate the presence of some cations, like (OH) that are present in many minerals and the less easily detectable by Raman spectrometry.

The infrared range is subdivided into three ranges:
Near Infrared (wavelength range: 12500-4000 cm-1 // 0.8-2.5 µm);
Mid Infrared (wavelength range: 4000-400 cm-1 // 2.5-25 µm);
Far Infrared (wavelength range: 400-10 cm-1 // 25-1000 µm).

The region of the near Infrared is favorable for the identification of the typical bands of some chemical groups or ions such as H2O (1.4 – 1.9 µm), OH (2.2 – 2.7 µm), and CO32- (1.9 – 2.0; 2. 17 – 2.3 µm). These absorption bands it can be used for the qualitative or semi quantitative analysis of these groups.

In the mid Infrared range, the absorption bands are normally due to the various minerals atomic groups. The mid infrared spectra of the mineral always bring significant information about the functional groups that constitute it.

Materials and methods

The mid-IR spectra were collected with a Bruker Vertex 70 Fourier-transform infrared (FT-IR) spectrometer with a spectral resolution ranging between 2-4 cm-1 and the spectral range between 370-7000 cm-1. The measurements were taken at room temperature using a KBr pellet technique. The infrared spectra were analyzed with an OPUS 6.5 software and for the resulting spectra, we choose the type of absorption spectrum. The fitting procedure of the spectra was not used.

The samples were finely powdered to allow the analysis with the FT-IR spectrometer (KBr pellet technique).