Figure 2
From: First experimental evidence of the piezoelectric nature of struvite
(a) Randomly oriented domains before poling in d.c. field. The structure of these domains is analogous to that presented in Ref. 20. (b) Single-domain state after poling in d.c. field represented by homogenous orientation of the optical indicatrix in the crystal. This homogenous orientation, observed after removing electrodes from the surfaces of poled crystal, indicates the permanent state of polarization after all piezoelectric measurements utilizing resonance method (Fig. 3).
