Nuclear spin relaxation in hydrogen: II. The Liquid

✍ Scribed by Myer Bloom

• Publisher: Elsevier Science
• Year: 1957
• Weight: 507 KB
• Volume: 23
• Category: Article
• ISSN: 0031-8914
• DOI: 10.1016/s0031-8914(57)92537-5

✦ Synopsis

The proton spin relaxation time tl for H2 liquid has been measured as a function of temperature and otho-para concentration. For normal H2, tx is found to be 0.18 second at 20.4°K and is found to increase with decreasing temperature and decrease with decreasing ortho-H2 concentrations. Calculations show that the translational motion of the H2 molecules contributes negligeably to tl, and that the usual model used to explain the contribution to tl from reorientations of the molecules fails to explain the observed temperature and ortho-para concentrations dependences. The results are shown to be closely related to the behavior of tl in H2 gas (article I). Measurements on HD liquid show a tl of about 35 second. This is interpreted as being due to the translational motion of the molecules relative to one another, an argument being presented to show that the rotational contribution to tl is negligeable for HD at the temperatures studied.