Boson Peak Investigation of LiCl-H2O System Using Terahertz Time-Domain Spectroscopy

The complex dielectric constant of 17.3 mol% lithium chloride aqueous solution, which is a typical hydrogen-bonded glass system, was determined from 291 K to 14 K using terahertz time-domain spectroscopy. The boson peak appeared at 1.3 THz at 14 K, suggesting that the determinant of boson peak frequency is hydrogen bonds between water molecules.