Adiabatic potential energy curves of [OH]⁶⁺ as a function of internuclear distance R. Panel a: calculated adiabatic potential energy curves for the lowest 20 ²Σ⁺ and 14 ²Π molecular states for n = 3, 4, 5 and 6 channels, panel b: potentials of ²Δ, ²Φ, and ²Γ molecular states for n = 3, 4, 5, and 6 channels, and panel c: adiabatic potentials near the vicinity of the avoided crossings for n = 4 and n = 5 channels.