Structure and dielectric properties of aqueous solutions of hydrogen peroxide

Resolving the controversy on the glass transition temperature of water?

“…Their dielectric relaxation times  D of less than 10 -10 s and superposing on each other are presented at the very bottom in Fig.7. The relaxation times from microwave measurements of solution of hydrazine mentioned in a previous section [48,49] overlap the bulk water data, as well as the relaxation times deduced from diffusion of bulk water data [83,95]. The lines are VFTH fits to the data of the hydrazine solutions published by Minoguchi et al [20,21].…”

“…Dashed line is eq.(6). open circles and open triangles) from [92,93,79,94] and the relaxation times deduced from diffusion data (cyan solid triangles) [83,95]; just above (green crossed diamonds) the relaxation times from microwave measurements of solution of hydrazine [48,49]. The violet and green lines are VFTH fits to the data of the hydrazine solutions published by Minoguchi et al [20,21].…”

“…The temperature dependence of   from dielectric study of Minoguchi et al and from microwave measurements [48,49] was fitted by the Vogel-Fulcher-Tammann-Hesse equation. The T g obtained as the temperature at which   =100 s for the solutions with 20, 26.5, and 33 mol % N 2 H 4 are almost identical with values of 136.3, 135.6, and 137.6 K respectively, and not far from T g =125 5 K of neat N 2 H 4 .…”

Hydration and Seamless Integration of Hydrogen Peroxide in Water

“…25−28 Although pure H 2 O 2 and H 2 O have similar freezing points 1,2 and dielectric constants, 4 their mixtures have a freezing point minimum near −50 °C, and both pure liquid H 2 O 2 and aqueous H 2 O 2 are more readily supercooled than pure water. 1,2 Such mixtures also have a larger dielectric constant 15 and longer relaxation times 16,17 than water, as well as a negative excess enthalpy, entropy, and Gibbs energy of mixing. 3,4 Similarities between H 2 O 2 and water are apparent in the vibrational spectra of H 2 O 2 in the vapor, 5,12 liquid, 11,14 and solid 13 phases, as well as solid H 2 O 2 dihydrate 23,24 and liquid aqueous H 2 O 2 solutions.…”

“…The similar chemical structures of hydrogen peroxide (H 2 O 2 ) and water (H 2 O) suggest that their mixtures may be uniquely compatible. Previous thermodynamic, − structural, ,− spectroscopic, ,,,,− and theoretical ,− studies of pure H 2 O 2 − ,,− and its aqueous mixtures ,,,,,,,− have revealed some striking similarities between H 2 O 2 and water but have not measured the hydration-shell spectrum of dilute aqueous H 2 O 2 or quantified the influence of H 2 O 2 on water structure. Here, we do so by using Raman multivariate curve resolution (Raman-MCR) spectroscopy, revealing four distinct sub-bands in the OH stretch region of dilute aqueous H 2 O 2 , whose assignments are aided by the previously reported crystal structure and the vibrational spectra , of solid H 2 O 2 ·2H 2 O as well as our own vibrational frequency calculations.…”