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Aqueous charge injection in forms of electrons, protons, lone pairs, ions, and molecular dipoles by solvation is ubiquitously important to our health and life. Pursuing fine-resolution detection and consistent insight into solvation dynamics and solute capabilities has become an increasingly active subject. This treatise shows that charge injection by solvation mediates the O:H-O bonding network and properties of a solution through O:H formation, H↔H fragilization, O:⇔:O compression, electrostatic polarization, H2O dipolar shielding, solute-solute interaction, and undercoordinated H-O bond contraction. A combination of the hydrogen bond (O:H-O or HB with ':' being the electron lone pairs of oxygen) cooperativity notion and the differential phonon spectrometrics (DPS) has enabled quantitative information on the following: (i) the number fraction and phonon stiffness of HBs transiting from the mode of ordinary water to hydration; (ii) solute-solvent and solute-solute molecular nonbond interactions; and (iii) interdependence of skin stress, solution viscosity, molecular diffusivity, solvation thermodynamics, and critical pressures and temperatures for phase transitions. An examination of solvation dynamics has clarified the following: (i) the excessive protons create the H↔H or anti-HB point breaker to disrupt the acidic solution network and surface stress. (ii) The excessive lone pairs generate the O:⇔:O or super-HB point compressor to shorten the O:H nonbond but lengthen the H-O bond in H2O2 and basic solutions; yet, bond-order-deficiency shortens and stiffens the H-O bond due H2O2 and OH− solutes. (iii) Ions serve each as a charge center that aligns, clusters, stretches, and polarizes their neighboring HBs to form hydration shells. (iv) Solvation of alcohols, aldehydes, complex salts, carboxylic and formic acids, glycine, and sugars distorts the solute-solvent interface structures with the involvement of the anti-HB or the super-HB. Extending the knowledge and strategies to catalysis, solution-protein, drug-cell, liquid-solid, colloid-matrix interactions and molecular crystals would be even more fascinating and rewarding. [ABSTRACT FROM AUTHOR]

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]

[Display omitted] • Hydration dissolves an organic trunk into molecular dipoles wrapped with lone pairs and protons. • Solute interacts with solvent via O:H attraction, H ↔ H and O:⇔:O repulsion, with polarization. • Polarization shortens and stiffens the H-O but the O:H responses to polarization contrastingly. • Repulsion disrupts the bonding network and surface stress by fragmentation of the solution. Interaction between an organic molecular solute and its hydrating H 2 O molecules is of great importance to processes varying from cryopreservation, denaturation of protein and DNA, and drug-cell interaction, to chemical, healthcare, and food and pharmaceutical sciences and technologies. However, the nature and functionality of the interfacial states, at the sub-molecular level, are particularly poorly known. On the views of solvation charge injection, electronic polarization, and bonding network disruption, we show experimental evidence for the interfacial supersolidity and its functionality on the performance of solutions. The asymmetrically distributed lone pairs and protons of the molecular solute interact with their unlike or alike of its hydrating H 2 O molecules to initiate the O:H attraction, H ↔ H repulsion or O:⇔:O compression associated with the molecule dipolar polarization, and solute–solute repulsion, without involvement of charge sharing or regular bond formation. Polarization lengthens the hydrating O:H and shortens the H-O, and repulsion does however the partitioned O:H-O bond contrastingly, which not only enriches the THz phonons but also results in the interfacial supersolidity characterized at H-O oscillating frequency ∼3450 cm−1. Solvation investigation of acids, alcohols, aldehydes, glycines, and sugars confirmed the prediction of the interfacial supersolidity and estimation of hydration cell size and the involvement of solute–solute repulsion. The solute dipolar polarizability distorts and the interfacial H ↔ H or O:⇔:O repulsivity disrupts the hydrogen bonding network. The bond relaxation, polarization, structure distortion, and network disruption modulate the hydrophilicity, surface stress, solubility, and solution viscosity. Findings not only improve the comprehension of the dynamics of molecular hydration and the functionality of the solutions but also offer efficient spectral means for identification and quantification of the interfacial hydration cell size and its supersolidity. [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]