Nuclear level mixing resonances on non-axially symmetric systems

For several years, nuclear Level Mixing Resonances (LMR) have been well studied, both theoretically [1,2] and experimentally [3,4]. The experimental results show that LMR is a very powerful technique to determine the static quadrupole interaction frequencies of long living isomers (10 ns up to 100 ms). The LMR formalism has been developed for isomers implanted in a solid host, providing an axially symmetric electric field gradient (EFG). In this paper, the theory has been elaborated to non-axially symmetric systems (η≠0). It will be shown that these systems have some special features, for example the possibility to derive the asymmetry η of the EFG if its orientation (, γ) in the LAB system is known.