In the title hydrated mol-ecular salt, C3H8N(+)·C2HO4 (-)·0.5H2O, the water O atom lies on a crystallographic twofold axis. The C=C-C-N torsion angle in the cation is 2.8 (3)° and the dihedral angle between the CO2 and CO2H planes in the anion is 1.0 (4)°. In the crystal, the hydrogen oxalate ions are linked by O-H⋯O hydrogen bonds, generating [010] chains. The allyl-ammonium cations bond to th...

A graded selection of hydrogen bonds and halogen bonds allows for the isolation of 2 : 1 : 1 ternary cocrystals of the general form 4-nitrobenzamide : diacid : 1,4-dihalogenated benzene, which are mediated by the amide-acid and I···O2N supramolecular synthons.

Halogen bonds (X-bonds) are shown to be geometrically perpendicular to and energetically independent of hydrogen bonds (H-bonds) that share a common carbonyl oxygen acceptor. This orthogonal relationship is accommodated by the in-plane and out-of-plane electronegative potentials of the oxygen, which are differentially populated by H- and X-bonds. Furthermore, the local conformation of a peptide...

In the present work, the sensitivity to the moisture (hygroscopisity) is studied for 3,4-dinitropyrazole (DNP) as a famous energetic molecule. All of the DNP-H2O complex systems (1-3) as well as individual molecules were optimized and bond lengths, bond angles, dihedral angles, charge transfer and stability via NBO analysis, corrected interaction energies with ZPE + BSSE and hydrogen bonds anal...

Evidence from proteins and peptides supports the conclusion that intrapeptide hydrogen bonds stabilize the folded form of proteins. Paradoxically, evidence from small molecules supports the opposite conclusion, that intrapeptide hydrogen bonds are less favorable than peptide-water hydrogen bonds. A related issue-often lost in this debate about comparing peptide-peptide to peptide- water hydroge...

The non-centrosymmetric crystal structure of the novel semi-organic title compound, C(2)H(5)N(4) (+)·NO(3) (-), is based on alternating layers of 4-amino-1H-1,2,4-triazolinium cations (formed by parallel chains of cations mediated by weak C-H⋯N hydrogen bonds) and nitrate anions inter-connected via linear and bifurcated N-H⋯O hydrogen bonds and weak C-H⋯O hydrogen bonds. N-H⋯N hydrogen bonds li...

Hydrogen bonds play major roles in biological structure and function. Nonetheless, hydrogen-bonded protons are not typically observed by X-ray crystallography, and most structural studies provide limited insight into the conformational plasticity of individual hydrogen bonds or the dynamical coupling present within hydrogen bond networks. We report the NMR detection of the hydrogen-bonded proto...

In the title compound, C(17)H(20)BrClNO(4)P, inter-molecular C-H⋯O and N-H⋯O hydrogen bonds form centrosymmetric R(2) (2)(10) dimers linked through O-H⋯O inter-molecular hydrogen bonds, which form centrosymmetric R(2) (2)(16) dimers. All these hydrogen bonds form chains along [010]. In addition, the crystal structure is stabilized by weak C-H⋯Br hydrogen bonds. The very weak intramolecular N-H⋯...