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An incorporation of the hydrogen bond (O:H O or HB) cooperativity notion, contact angle detection, and the differential phonon spectrometrics (DPS) has enabled us to gain refined information on the HCl, KCl and KOH solvation resolved solute-solvent molecular interactions and the solution surface stresses. Results show that ionic polarization stiffens the solvent H O bond phonon from 3200 to 3480 cm −1 in the hydration shells. The HO − in alkaline solution, however, shares not only the same H O phonon redshift of compressed water from 3200 to < 3100 cm −1 but also the dangling bonds of H 2 O surface featured at 3610 cm −1 . Salt and alkaline solvation enhances the solution surface stress by K + and Cl − ionic polarization. The excessive H + proton in acid solution forms a H↔H anti-HB that depresses the solution surface stress, instead. The solute capability of transforming the fraction of the O:H O bonds of the solvent matrix is featured by: f H = 0 and f x ∝ 1-exp(-C/C 0 ) (x = HO − , K + and Cl − ) towards saturation. Exercises not only confirm the presence of the H↔H anti-HB point fragilization, the O:⇔:O super-HB point compression, and ionic polarization dominating the performance of the respective HCl, KOH, and KCl solutions, but also demonstrate the power of the DPS that enables high resolution of solute-solute-solvent interactions and correlation between HB relaxation and solution surface stress. [ABSTRACT FROM AUTHOR]

Raman phonon differential spectrometrics (DPS) and contact angle measurements resolved that solvation of the NaX (X = HSO 4 , NO 3 , ClO 4 , SCN) complex salts stiffens the H O stretching phonon from 3200 to ~ 3500 cm − 1 and softens the O:H nonbond phonon from 180 to ~ 70 cm − 1 with rising of solution surface stress. The solute capability of bond transition in terms of the fraction coefficient, follows the relation, f NaX (C) ∝ 1-exp(− C/C 0 ) towards saturation, with C being the solute concentration and C 0 the decay constant. Observations evidence that: (i) the solute ionic field electrification aligns, stretches, and polarizes its neighboring H 2 O molecules, which shortens the H O bond but lengthens the O:H nonbond via O O Coulomb repulsion; (ii) the effect of X − electrification on the O:H O bond relaxation varies with solute type and solute concentration. Exercises not only verify the essentiality of solvent O:H O bond cooperative relaxation and polarization but also demonstrate the power of DPS that resolves processes occurred upon solvation. [ABSTRACT FROM AUTHOR]

Low-temperature Raman spectroscopy revealed that sugar solvation depresses the critical temperature for homogeneous ice nucleation ( T N ) whose depression extent follows the order of: trehalose > glucose > fructose at the same concentration and the extent of T N depression for a specific sugar is proportional to its concentration. We attribute the T N depression to the O:H vibration mode redshift induced by the solute dipolar polarization and distortion of the solvent hydrogen bond (O:H O or HB with “:” being the electron lone air of oxygen). The O:H phonon redshift lowers the Debye temperature of the O:H specific heat and disperses the quasisolid-phase boundary and the associated T N . [ABSTRACT FROM AUTHOR]

Solvation of acid, base, and salt is ubiquitously important to all subject areas in chemistry, health care and life science. However, fine resolution of the solvation dynamics, solute-solvent molecular interactions, and solute capability of transforming the hydrogen bond (O:H O, or HB) and surface stress remain great challenge. Incorporating the notion of O:H O bond cooperativity with a strategy of differential phonon spectroscopy (DPS) has enabled resolution on the fraction and stiffness of the solvent HB from the mode of water to the hydration shells upon NaOH, NaI and HI solvation. Results show that Na + and I + ionic polarization shortens the H O bond and stiffens its phonon from 3200 to 3500 cm − 1 in the hydration shells. The H + in the HI solution forms a H ↔ H anti-HB that disrupts the solution network and surface stress. The excessive electron lone pairs of OH – form the O : ⇔ : O super-HB that compresses the network, sharing the same effect of mechanical compression shifting the H O phonon from above 3100 cm − 1 to its below; the solute H O bond performs the same to the H O dangling bond at surface featured at 3610 cm − 1 . The fraction coefficients or phonon abundance transition, f H = 0, f HO ∝ C, and f x ∝ 1-exp(− C/C 0 ) (x = Na + and I − and C the solute concentration) towards saturation, feature the solute capability of HB transformation. Practice not only confirms the essentiality of the H ↔ H anti-HB point fragilization, the O : ⇔ : O super-HB point compression, and the ionic polarization to the performance of the respective HI, NaOH, and NaI solutions, but also demonstrate the power of the DPS that enables fine-resolution of solvation dynamics and solute capabilities. [ABSTRACT FROM AUTHOR]