Forward period spacing (ΔΠ, upper panels) and logarithm of the kinetic energy (E_kin, lower panels) in terms of the periods of ℓ = 1 pulsation modes for a 1.29 M_⊙ ONe-core WD model at T_eff ∼ 11 600 K. Left panels: case in which crystallization was not taken into account (NC case). Central panels: same quantities for the situation in which crystallization was considered but phase separation was not (LH case). Right panels: case in which both crystallization and phase separation were taken into account (LH+PS case). In the three cases, the percentage of the crystallized mass is indicated. In the upper panels, horizontal red dashed lines correspond to the asymptotic period spacing.