Figure 5

(a–d) The temperature-dependent Raman spectra for the four structures from 20 to 90 °C. The red solid and green dashed circles was used to display the transition process and the abnormal variation of Raman intensity.
(a–d) The temperature-dependent Raman spectra for the four structures from 20 to 90 °C. The red solid and green dashed circles was used to display the transition process and the abnormal variation of Raman intensity.