  Trapping of microparticles and aerosols is of great interest for physics and
chemistry. We report microparticle trapping in multipole linear Paul trap
geometries, operating under Standard Ambient Temperature and Pressure (SATP)
conditions. An 8-electrode and a 12-electrode linear trap geometries have been
designed and tested with an aim to achieve trapping for larger number of
particles and to study microparticle dynamical stability in electrodynamic
fields. We report emergence of planar and volume ordered structures of the
microparticles, depending on the a.c. trapping frequency and particle specific
charge ratio. The electric potential within the trap was mapped using the
electrolytic tank method. Particle dynamics was simulated using a stochastic
Langevin equation. We emphasize extended regions of stable trapping with
respect to quadrupole traps, as well as good agreement between experiment and
numerical simulations.
