THEORETICAL-STUDY OF THE RESONANT BEHAVIOR OF AN ION CONFINED TO A POTENTIAL WELL IN A COMBINATION OF AC AND DC MAGNETIC-FIELDS

Numerical solutions are presented to the equation of motion for an ion confined to a region of space by a restoring force and subject to DC and AC magnetic fields. We have expanded on the theoretical work of Durney et al. [1988] by including a potential well as a confining factor. This additional term in the equation of motion, being nondissipative, could allow for the buildup of stored energy within the system to a level necessary for a macroscopic resonant phenomenon. Resonant behaviour has been studied, including calculation of the trajectory and energy (kinetic and potential) of a confined ion, with emphases on the appearance of both amplitude and frequency windows. The results are discussed in relation to ion transport through transmembrane channels exposed to magnetic fields. When realistic values of the frictional and restoring-force coefficients are considered, all predicted resonant behaviour disappears, except at very high field strengths. (C) 1993 Wiley-Liss, Inc.