Proton spin-lattice relaxation times of some halogenated methanes

Abstract

The proton spin-lattice relaxation times of some halogenated methanes have been measured as a function of concentration in carbon disulphide at 25°C and 29.9 Mc/sec. In all the cases studied, except one, the observed relaxation times can be explained by dipolar coupling. For chloroform it is proposed that the spin-rotation interaction is important, and that the spin-rotation interaction constant is about 4 Kc/sec. The variation of T₁ with concentration is not explained satisfactorily by Hill's theory of viscosity, but conforms well to a modification of Debye's theory.