Nujol

Nujol is a brand of mineral oil by Plough Inc., cas number 8012-95-1, and density 0.838 g/mL at 25 °C, used in infrared spectroscopy. It is a heavy paraffin oil so it is chemically inert and has a relatively uncomplicated IR spectrum, with major peaks between 2950-2800, 1465-1450, and 1380–1370 cm. The empirical formula of Nujol is hard to determine exactly because it is a mixture but it is essentially the alkane formula C
nH
(2n + 2) where n is very large.