Zeeman Splitting of the Nuclear Quadrupole Resonance Line of Iodine

Abstract

Zeeman patterns of the nuclear Quadrupole resonance line of I 127 were studied with a single crystal of iodine at medium and weak magnetic fields. The asymmetry parameter of coupling, η, and the angle between bond axis of the iodine molecule and crystallographic c axis, ϕ, were determined from the pattern at a medium magnetic field of about 120 gauss. The result was η=-0.16±0.01 at 14°C when crystallographic b axis was chosen as x axis and ϕ=31°38'±60'. The absolute value of η is in accord with the value obtained by the two resonance frequencies, i.e. 0.151±0.001 at 11°C, ϕ agrees with that obtained by the X-ray diffraction, 32°4'. At a weak magnetic field, Zeeman patterns of the fine structure of iodine were examined at three directions of magnetic field against the iodine crystal, i. e. the b axis, the c axis and the direction of 60° from the b axis in the b c plane. Behaviour of the superregenerative detector used for these N.Q.R. measurements was studied and the observed shape of the resonance line is discussed.