GEHLKEN, P.-L. & SUSSE, P. (1999):
InfRed – an infrared spectroscopical database.

Infrared spectroscopy has become a very powerful tool of mineral identification. However, compilations of standard reference spectra covering a wide range of minerals are not available so far. This database is intended to fill this gap.

InfRed contains spectral data measured with our own experimental setup as well as data taken from literature. The latter are taken from the collections of Moenke, van der Marel & Beutelspacher, Gadsden, and Jones & Jackson. Our own spectra were recorded in transmission mode between 4000 cm-1 and 400 cm-1 with a Mattson 3000 type Fourier transform infrared spectrometer. In some special cases a Perkin-Elmer 683 type spectrophotometer was employed over a range of 4000 cm-1 to 250 cm-1. 32 Scans were taken using a DTGS detector at a resolution of 4 cm-1. The specimens were usually embedded in KBr. Other techniques were used only if required by the nature of the sample. The spectral data were obtained with a „peak-pick“ program, followed by manual examination in order to include significant shoulders and other diagnostic features.

One mineral entry in InfRed consists of the following data: Mineral name, origin of sample (sedimentary, metamorphic, synthetic etc.), chemism (up to 7 atoms), infrared spectrum (up to 8 peaks), information about the kind of sample preparation, and the literature reference.

InfRed comes with a specially written software that allows search for one or a combination of the following parameters: Mineral name, chemistry (up to 7 atoms), and the infrared absorption data (up to 8 bands with variable input band width). Presently the database consists of about 2000 entries, covering a range of about 1000 different mineral species and some 100 other related inorganic compounds.

With some practice, the use of this database will enable the analyst to determine the kind of his specimen right away, or at least, to narrow it down to a likely few, the literature references of which are given in the database. The literature with the original spectra or a full set of infrared spectroscopic data should then lead to an unequivocal result.