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Energy density and structure stability are of key concerns in devising energy materials such as CNHO molecular crystals and the emerging cyclo-N 5 − complexes for desired explosive functionalities with a mechanism being open for exploration. An extension of the recent progress in solvation suggests that a combination of the intermolecular hydrogen bond (X:H–Y or HB with ':' being electron lone pair of X, Y = O or N) tension and the super-HB (X:⇔:Y) or anti-HB (H↔H) compression not only stabilizes the structure but also stores excessive energy by shortening the intramolecular bonds. The presence of the X:H constrains and the presence of the X:⇔:Y and/or H↔H fosters the explosion. Observations suggest that the absence of X:H–Y tension results in the spontaneous aquatic explosion of alkali metals and molten alkali halides. The lack of X:⇔:Y repulsion fosters no explosion of the molten NaCl in liquid NH 3 , nor the molten Na 2 CO 3 salt or H 3 BO 3 acid in water. The findings shall offer guidelines for devising efficient energy materials and reconciling the nature origin of water ice, aqueous solutions, and explosive energy materials – significance of electron lone pairs and protons. The combination of the hydrogen-bond (X:H–Y) tension and the super-HB (X:⇔:Y) or the anti-HB (H↔H) repulsion not only stabilizes the structure but also stores energy by shortening the intramolecular covalent bonds. The X:H tension constrains and the X:⇔:Y repulsion fosters explosion. Unlabelled Image • Segmental cooperativity of the X:H-Y oscillator pair dictates the behavior of aqueous solutions. • Excessive H+ or lone pairs ":" derive H↔H or X:⇔:Y repulsion in molecular crystals/liquids. • X:⇔:Y or/and H↔H repulsion and X:H-Y tension governs the stability and energy of crystals. • The absence/presence of the X:H-Y tension fosters the spontaneous/constrained explosion. [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]

[Display omitted] • An ion forms a supersolid hydration cell by screened polarization of H 2 O dipoles. • Ionic polarization shortens and stiffens the H-O while does the O:H contrastingly. • A cation keeps its hydration volume invariant without being interfered by others. • Inter-anion repulsion reduces anionic hydration volume by weakening its field. • Cation/anion polarizability governs the linear/nonlinear term of Jones-Dale viscosity. Understanding the performance of individual ions in salt solutions and the consequence of ionic hydration on hydrogen bonding network distortion, surface stress, and solution viscosity remains great challenge. We show herein findings pertained to alkali halide YX solutions using differential phonon spectroscopy (X = Cl, Br, I; Y = Li, Na, K, Rb, Cs): (i) an ion occupies eccentrically the tetrahedrally-coordinated interstitial of water to form a (±:4H 2 O:6H 2 O) hydration cell without bonding to H 2 O molecules; (ii) ionic polarization shortens and stiffens the H-O bond while does the O:H nonbond contrastingly; (iii) the screening of the hydrating water dipoles limits the cation hydration cell to be size invariant while the inter-anion repulsion reduces its hydration volume by weakening the anionic long-range electric field when the ionic separation shrinks; and (iv) the polarization of cation and anion dictates respectively the linear and the nonlinear part of Jones-Dale's viscosity and surface stress. Findings would provide profound impact to the understanding and deep engineering of water, ice, and aqueous solutions. [ABSTRACT FROM AUTHOR]