We study the Pöschl-Teller equation in complex domain and deduce infinite families of T Q and Bethe ansatz equations, classified by four integers. In all these models the form of T is very simple, while Q can be explicitly written in terms of the Heun function. At particular values there is a interesting interpretation in terms of finite lattice spin-XXZ quantum chain with ∆ = cos π L (for free-free boundary conditions), or ∆ = − cos π L (for periodic boundary conditions). This result generalises the findings of Fridkin, Stroganov and Zagier. We also discuss the continuous (field theory) limit of these systems in view of the so-called ODE/IM correspondence.PACS number: 05.50+q, 02.30.Ik