  In present work, we discuss the effect of Coulomb interaction to the dynamics
of two-particle system bound in various traps. The strategy of including
Coulomb interaction into the quantization condition of trapped system is
discussed in a general and non-perturbative manner. In most cases, Coulomb
corrections to quantization condition largely rely on numerical approach or
perturbation expansion. Only for some special cases, such as the spherical hard
wall trap, a closed-form of quantization condition with all orders of Coulomb
corrections can be obtained.
