Boson Peak Analysis of Glucose Polymers via Terahertz Time-Domain Spectroscopy

Terahertz time-domain spectroscopy (THz- TDS) was performed on cellulose and paramylon ester to detect the boson peak (BP), which is a universal excitation characteristic of glass-forming substances. In the infrared spectrum, BP is observed in a plot of α(V)/V
²
vs. frequency ( v), where α(V) is the absorption coefficient. The BP of the paramylon ester is observed at 0.75 THz, which is lower than that for other glucose glasses. The low BP frequency of the paramylon ester suggests that the OH groups affect the BP frequency. This result indicates that the hydrogen bond contributes significantly to the BP frequency.