Figure 2

(a) 2θ single-crystal XRD plot on the (003) plane of NTO. The inset shows the θ scan that corresponds to the (006) Bragg peak, which clearly reveals the single crystalline phase of NTO with a single Gaussian peak and a narrow FWHM feature. (b) Temperature-dependent powder XRD plot, measured after finely crushing a few NTO crystals. Details of all the peak positions and corresponding (hkl) values can be found in Table 1 of the Supplementary Information.