The glass forming molecular liquid ortho??terphenyl has been investigated by 2H??NMR techniques providing spin??relaxation times (T 1, T 2), and spin??alignment data which yield information on the time scale and geometry of ultra??slow molecular reorientation. The main results are as follows: The primary glass transition (α process) is characterized by rotational molecular jumps with a jump size distribution weighted in favor of large jump angles, and ...
