Saturation of the Nuclear Magnetic Resonance Absorption and the Spin-Lattice Relaxation Time in Solid Hydrogen

A new type of anomaly was found in the saturation behavior of the nuclear magnetic resonance absorption in solid hydrogen with various ortho-para ratios. In the central peak, the saturation curve showed anomalous dependence on rf field and the line width decreased with increasing rf field, while in the side peak, they were of rather normal behaviors. The spin-spin and spin-lattice interactions were discussed in detail and a possible explanation of the anomalies was obtained. They could be interpreted as a sort of inhomogenous saturation. The relaxation times in the side peak and in the central peak were calculated from the experimental saturation curves using a saturation formula obtained from the above treatments. It was found that the central peak has relaxation times distributed over a range from milliseconds to seconds with the maximum value inversely proportional to ortho concentration and temperature, and that the side peak has, on the contrary, a single relaxation time