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About this book

This book highlights the latest advances and outlines future trends in aqueous solvation studies from the perspective of hydrogen bond transition by charge injection, which reconciles the solvation dynamics, molecular nonbond interactions, and the extraordinary functionalities of various solutes on the solution bond network and properties. Focus is given on ionic and dipolar electrostatic polarization, O:H nonbond interaction, anti-HB and super-HB repulsion, and solute-solute interactions. Its target audience includes researchers, scientists, and engineers in chemistry, physics, surface and interface science, materials science and engineering.

Table of Contents

Frontmatter

Chapter 1. Introduction

Abstract
Overwhelming contributions have been made since two-century-long ago to understanding the solvation dynamics, solute-solute and solute-solvent molecular interactions, and solution properties from various perspectives. Limited knowledge about the solvent water structure and hydrogen bond cooperativity (O:H–O or HB with “:” being the nonbonding electron lone pairs pertained to oxygen upon sp3-orbital hybridization) hindered the progress. Amplification of the phonon spectroscopy to spectrometrics and of the perspective of molecular motion to hydration bonding dynamics would be necessary towards the solute capabilities of transiting the ordinary O:H–O bond to the hydrating states and their impact to the performance of solutions.
Chang Q Sun

Chapter 2. Differential Phonon Spectrometrics (DPS)

Abstract
An incorporation of the hydrogen bond cooperativity theory to the DPS strategy and surface stress (contact angle) detection could resolve the solvation bonding and nonbonding dynamics and solute capabilities. The enabled information includes bond length and stiffness transition, electron polarization, and the fraction of bonds transformed from the mode of ordinary water to the hydration shells. A combination of the DPS and the ultrafast IR spectroscopy would be more revealing towards solute-solvent and solute-solute molecular interactions, solute capabilities, and solution properties. The DPS is focused on the solvation O:H–O segmental cooperative bonding dynamics and the ultrafast IR on molecular motion dynamics by measuring phonon relaxation time.
Chang Q Sun

Chapter 3. Theory: Aqueous Charge Injection by Solvation

Abstract
Solvation is a process of aqueous charge injection in the forms of H+, electrons, electron lone pairs, cations, anions, or  molecular dipoles with long- and short-range interaction. A solute interacts with its neighboring H2O molecules through the O:H vdW, O:⇔:O super-HB compression, H↔H anti-HB fragilization, ionic or dipolar polarization with screen shielding, and solute-solute interaction and their combinations. The hydration H2O dipoles tend to be aligned oppositely along the electric field screen in turn the electric fields of the solute. The ionic size, charge quantity, and the numbers and spatial distribution of H+ and “:” determine the form of solute-solvent interaction. A solute may be sensitive or not to interference of other solutes depending on the solute size and its extent of screening. The intermolecular nonbond and intramolecular bond cooperative relaxation determines the performance of a solution in terms of surface stress, solution viscosity, energy absorption-emission-dissipation at solvation, solvation temperature, thermal stability, critical pressures and pressures for phase transition.
Chang Q Sun

Chapter 4. Lewis Acidic Solutions: H↔H Fragilization

Abstract
Solvation dissolves the HX into an H+ and an X. The H+ bonds to a H2O to form a firm H3O+ and a H↔H anti − HB point breaker. The H–O bond due H3O+ is 3% shorter and the associated O:H nonbond is 60% longer than normal. The H↔H compression shortens its nearest O:H nonbond by 11% and lengthens the H–O by 4%. The X point polarizer shortens the H–O bond and stiffens its phonon but relax the O:H nonbond oppositely in the supersolid hydration shell. The X solute capability of bond transition follows the I > Br > Cl order in the form of fx(C) ∝ 1 − exp(−C/C0) towards saturation because of the involvement of the X↔X interaction that weakens the hydration-shell electric field at higher concentrations. However, the H+ neither hops or tunnels freely nor polarize its neighbors, fH(C) = 0. The H↔H has the same effect of heating on the surface stress and solution viscosity disruption.
Chang Q Sun

Chapter 5. Lewis Basic and H2O2 Solutions: O:⇔:O Compression

Abstract
The OH and the H2O2 possess each two excessive pairs of electron lone pairs “:” that form an O:⇔:O super−HB upon solvation. The O:⇔:O compression shortens the O:H nonbond and stiffens its phonon but relaxes the H–O bond oppositely. The H–O bond elongation emits energy to heat up the solution. Bond-order-deficiency shortens the solute H–O bond and stiffens its phonon to 3550 cm−1 for H2O2 and 3610 cm−1 for OH. However, the O:⇔:O compression annihilates the weak cationic polarization. The H2O2 is less than the OH capable of transiting the solvent H–O bonds and surface stress. The linear fraction coefficient f(C) suggests that the OH be less sensitive to other solutes. The resultant of solvent exothermic H–O elongation by O:⇔:O compression and the solute endothermic H–O contraction by bond order deficiency heats up the solutions. Observations evidence not only the significance of the inter-lone-pair interaction but also the universality of the bond order-length-strength (BOLS) correlation to aqueous solutions.
Chang Q Sun

Chapter 6. Hofmeister Salt Solutions: Screened Polarization

Abstract
Water dissolves salt into ions and then hydrates the ions in an aqueous solution. Hydration of ions deforms the hydrogen bonding network and triggers the solution with what the pure water never shows such as conductivity, molecular diffusivity, thermal stability, surface stress, solubility, and viscosity, having enormous impact to many branches in biochemistry, chemistry, physics, and energy and environmental industry sectors. However, regulations for the solute-solute-solvent interactions are still open for exploration. From the perspective of the screened ionic polarization and O:H–O bond relaxation, this chapter is focused on understanding the hydration dynamics of Hofmeister ions in the typical YI, NaX, ZX2, and NaT salt solutions (Y = Li, Na, K, Rb, Cs; X = F, Cl, Br, I; Z = Mg, Ca, Ba, Sr; T = ClO4, NO3, HSO4, SCN). Phonon spectrometric analysis turned out the f(C) fraction of bond transition from the mode of deionized water to the hydrating. The linear f(C) ∝ C form features the invariant hydration volume of small cations that are fully-screened by their hydration H2O dipoles. The nonlinear f(C) ∝ 1 − exp(−C/C0) form describes that the number insufficiency of the ordered hydrating H2O diploes partially screens the anions. Molecular anions show stronger yet shorter electric field of dipoles. The screened ionic polarization, inter-solute interaction, and O:H–O bond transition unify the solution conductivity, surface stress, viscosity, and critical energies for phase transition.
Chang Q Sun

Chapter 7. Organic Molecules: Dipolar Solutes

Abstract
The excessive number of H+ or “:” and their asymmetrical distribution determines the performance of their surrounding water molecules in a way different from that of ordinary water. The naked lone pairs and protons are equally capable of interacting with the solvent H2O molecules to form O:H vdW bond, O:⇔:O super–HB or H↔H anti-HB without charge sharing or new bond forming. Solvation examination of alcohols, aldehydes, formic acids, and sugars reveals that O:H–O formation enables the solubility and hydrophilicity of alcohol; the H↔H anti-HB formation and interface structure distortion disrupt the hydration network and surface stress. The O:H phonon redshift depresses the freezing point of sugar solution of anti-icing.
Chang Q Sun

Chapter 8. Multifield Coupling

Abstract
Transiting the NaX/H2O solutions from liquid into ice VI (at PC1) and then into ice VII (PC2) phase at 298 K needs excessive pressures with respect to the same sequence of phase transition for pure water. PC1 and PC2 vary simultaneously with the solute type in the Hofmeister series order: I > Br > Cl > F ~ 0. However, the PC1 grows faster than the PC2 with the increase of NaI/H2O concentration, following the (P, T) path upwardly along the Liquid-VI phase boundary. The PC1 and PC2 meet then at the Liquid-VI-VII triple-phase junction at 3.3 GPa and 350 K. Observations confirmed that compression recovers the electrification-elongated O:H–O bond first and then proceeds the phase transitions, which requires excessive energy for the same sequence of phase transitions. Heating enhances the effect of salting on bond relaxation but opposite on polarization that dictates the surface stress of the solution. It is also confirmed that molecular undercoordination disperses the quasisolid phase boundaries and the room-temperature ice-quasisolid phase transition needs excessive pressure. Polarization by salt solvation and skin undercoordination and boundary reflection transit the phonon abundance-lifetime-stiffness cooperatively. An extension of the HB and anti-HB or super-HB clarifies the energetic storage and structural stability for the spontenous and constrained explosion of energetic carriers.
Chang Q Sun

Chapter 9. Concluding Remarks

Abstract
A combination of the O:H–O bond cooperativity, segmental DPS strategy, and contact-angle detection, etc., has enabled systematic quantification and clarification of the hydration bonding dynamics for HX acids, YOH bases and H2O2 hydrogen peroxide, YX, ZX2 and complex NaT salts, alcohols, organic acids, aldehydes, and sugars. Advancement of the theoretical and experimental strategies has enabled resolution of the solute capabilities of transiting the O:H–O bonds from the mode of ordinary water into the hydrating states in terms of phonon abundance, bond stiffness, and fluctuation order, and electron polarization. O:H vdW formation, H↔H point fragilization, O:⇔:O point compression, and ionic or dipolar polarization form the basic elements for molecular nonbond interactions. Nonbond-bond cooperativity and solute-solvent interfacial structure distortion govern the performance of the solutions in terms of surface stress, solution viscosity, molecular diffusivity, phonon lifetime, solution temperature, phase boundary dispersion, critical pressures and temperatures for phase transition under mutifield excitation.
Chang Q Sun

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