https://doi.org/10.1351/goldbook.08642
Infrared radiation of which vacuum wavenumbers range from approximately \(\pu{12800 cm-1}\) to \(\pu{4800 cm-1}\) and wavelengths range from approximately \(\pu{780 nm}\) to \(\pu{2500 nm}\).
Note:
The region is often divided into the silicon region between \(\pu{12800 cm-1}\) and \(\pu{9000 cm-1}\) (\(\pu{800 nm}\) and \(\pu{1100 nm}\)) and the lead sulfide region between \(\pu{9000 cm-1}\) and \(\pu{4000 cm-1}\) (\(\pu{1100 nm}\) and \(\pu{2500 nm}\)), where the names reflect the common detector for the region.
The region is often divided into the silicon region between \(\pu{12800 cm-1}\) and \(\pu{9000 cm-1}\) (\(\pu{800 nm}\) and \(\pu{1100 nm}\)) and the lead sulfide region between \(\pu{9000 cm-1}\) and \(\pu{4000 cm-1}\) (\(\pu{1100 nm}\) and \(\pu{2500 nm}\)), where the names reflect the common detector for the region.