Accurate quantification of hydration number for polyethylene glycol molecules

Guo Wei^{1, 2}, Zhao Lishan², Gao Xin¹, Cao Zexian², Wang Qiang^{2, †}

(color online) (a) Raman spectra of aqueous solutions of PEG 400 with different mass fractions of water. (b) Water content dependence of the peak position of the symmetrical stretching mode of CH₂ in the PEG 400 molecule. The arrow in panel (b) indicates labeled in Fig. 1(b).