Determination of sample temperature and temperature stability with 129Xe NMR.

The (129)Xe chemical shift of xenon dissolved in isotropic liquids is very sensitive to solvent density, which in turn is dependent on the sample temperature. Therefore, the (129)Xe chemical shift can be used as the basis of a thermometer for measuring actual sample temperatures in NMR experiments. Good accuracy can be achieved, but the thermometer is particularly useful in monitoring temperature stability. In the present case, carbon tetrachloride (CCl(4)), ethylbromide (C(2)H(5)Br), and deuterated chloroform (CDCl(3)) were chosen as solvents because of their large thermal expansion coefficient.