Solvents

 All FT spectrometers use a deuterium lock system for field stabilization, so it is essential to use solvents containing deuterium. The only common solvent excluded by the requirement is carbon tetrachloride. All the usual organic solvents are available in deuterated form, although some are rather expensive. It is wise to consider whether a cheaper alternative will suffice (chloroform, DMSO and D₂O are the cheapest solvents). Stocks of solvents are kept in the chemical stores and are available for general use; These solvents are of medium quality with respect to levels of deuteration; for proton work with small quantities of sample, higher grade solvents sealed in 0.5 ml vials can be purchased from various suppliers. When working with proton spectra of dilute samples, e.g. sub-milligram quantities, always consider where the signal from residual protonated solvent will occur. For solvents other than chloroform, the signal will be a multiplet due to coupling with deuterium and may fall in a rather inconvenient place. Another "impurity" signal to be aware of is that of water, which occurs in all solvents and often gives rise to a rather broad signal.

The following table lists some useful properties of the most commonly used solvents:
 
 

Solvent	dH/ppm	d(HOD)/ppm	dC/ppm	MeltingPoint/oC	BoilingPoint/oC
Acetone-d6	2.05	2.0	206.7, 29.9	-94	57
Acetonitrile-d3	1.94	2.1	118.7, 1.4	-45	82
Benzene-d6	7.16	0.4	128.4	5	80
Chloroform-d1	7.27	1.5	77.0	-64	62
Deuterium oxide-d2	4.80	4.8	-	3.8	101
Dichloromethane-d2	5.32	1.5	54.0	-95	40
N,N-dimethyl formamide-d7	8.03, 2.92, 2.75	3.5	163.2, 34.9, 29.8	-61	153
Dimethylsulfoxide-d6	2.50	3.3	39.5	18	189
Methanol-d4	4.87, 3.31	4.9	49.2	-98	65
Pyridine-d5	8.74, 7.58, 7.22	5.0	150.4, 135.9, 123.9	-42	116
Tetrahydrofuran-d8	3.58, 1.73	2.4	67.6, 25.4	-109	66
Toluene-d8	7.09, 7.00, 6.98, 2.09	0.4	137.9, 129.2, 128.3, 125.5, 20.4	-95	111