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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]

The H N bond in the TATB assembly exhibits excitingly negative compressibility and negative thermal expansivity because of the unprecedented O N coupling interactions. [Display omitted] • O:H N bond in TATB acts the same to O:H O in H 2 O upon compression and heating. • H N bond possesses negative compressibility and negative thermal expansibility. • Heating shortens C NH 2 and N H but does the C NO 2 and N O contrastingly. • The O/N:H nonbonds possess the regular compressibility and thermal expansivity. • The N O repulsion drives the unusual response of the O:H N bond to perturbation. Incorporating the mechanical and thermal perturbations to the Raman spectroscopy has enabled resolution to the response of the individually segmented C N 2H:2O N C interactions for the 1,3,5-triamona, 2,4,6-trinitorbenzene (TATB, C 6 H 6 N 6 O 6) assembly with ":" representing the electron lone pair of nitrogen or oxygen at the molecular interfaces. It is uncovered that: (i) the N H bond possesses the negative compressibility and negative thermal expansivity; (ii) the C (N 2H) bond undergoes both compressive and thermal contraction; (iii) the (O,N):H and rest interactions follow the regular compressibility and thermal expansivity. The unusual response of the H N bond in TATB to perturbation is the same to the H O segment of the O:H O bond of water ice and the N:H O bond of the cyclo -N 5 −:4H 3 O+ complexes, which proves that the O:⇔:N repulsion couples the inter-(O:H) and the intramolecular (H N) interactions and drives the O:H N to relax cooperatively in the segmental length, energy, and vibration frequency when subjecting to perturbation. Discoveries demonstrate not only the significance of molecular coupling interactions but also the power of mechanical and thermal perturbations that enable detailed information of individual bond relaxation, advancing the engineering in chemistry and devising of functional molecular materials. [ABSTRACT FROM AUTHOR]