THz for H2O and 9.5 THz for D2O, respectively. The tale of the L1 band must be overlapping with Peak III and resulted in changing their lineshapes. As a result, the fitting parameters of D2O become higher intensity and higher frequency than those of H2O. The original mode of the Peak III, located around 8 THz, has no corresponding vibrational mode in the spectra of liquid water.