We examine an unusual case where a neutral hydrogen atom acts as a hydrogen-bond acceptor. The association constant between trihexylsilane and perfluoro-tert-butanol was measured as ∼0.8 M(-1) in cyclohexane. Computations and experimental NMR data are consistent with a weak, but favourable Si-H···HO interaction.

Hexa-peri-hexabenzocoronene derivatives (HBCs) that have hydrogen-bonding functionalities (either amido or ureido groups) adjacent to the aromatic cores have been synthesized to study the effects of intracolumnar hydrogen bonds on the self-assembly behavior of HBCs. The hydrogen bonds effectively increased the aggregation tendency of these compounds in solution. In the bulk state, the typical c...

We have investigated the dynamics of the hydrogen bonds that connect the components of a [2]rotaxane in solution. In this rotaxane, the amide groups in the benzylic-amide macrocycle and the succinamide thread are connected by four equivalent N-H⋅⋅⋅O=C hydrogen bonds. The fluctuations of these hydrogen bonds are mirrored by the frequency fluctuations of the NH-stretch modes, which are probed by ...

The electronic nature of low-barrier hydrogen bonds (LBHBs) in enzymatic reactions is discussed based on combined low temperature neutron and x-ray diffraction experiments and on high level ab initio calculations by using the model substrate benzoylacetone. This molecule has a LBHB, as the intramolecular hydrogen bond is described by a double-well potential with a small barrier for hydrogen tra...

863-Pos Board B632 Hydrogen Bond Strength Modulates the Mechanical Strength of FerricThiolate Bonds in Rubredoxin Peng Zheng, Shin-ichi J. Takayama, A Grant Mauk, Hongbin Li. University of British Columbia, Vancouver, BC, Canada. It has long been recognized that hydrogen bonds formed by protein backbone amides with cysteinyl Sulfur atoms play important roles in modulating the functional and str...

PDZ domains are scaffolding modules in protein-protein interactions that mediate numerous physiological functions by interacting canonically with the C-terminus or non-canonically with an internal motif of protein ligands. A conserved carboxylate-binding site in the PDZ domain facilitates binding via backbone hydrogen bonds; however, little is known about the role of these hydrogen bonds due to...

In the title compound, C(17)H(18)N(4)O(5)·2C(3)H(7)NO, two solvent mol-ecules are linked to the main mol-ecule via N-H⋯O and O-H⋯O hydrogen bonds, forming a hydrogen-bonded trimer. Intra-molecular O-H⋯N hydrogen bonds influence the mol-ecular conformation of the main mol-ecule, and the two benzene rings form a dihedral angle of 10.55 (18)°. In the crystal, inter-molecular O-H⋯O hydrogen bonds l...

The hydrostatic compression of L-serine-d(7) has been studied to 8.1 GPa by neutron powder diffraction. Over the course of this pressure range the compound undergoes two phase transitions, the first between 4.6 and 5.2 GPa, yielding L-serine-II, and the second between 7.3 and 8.1 GPa, yielding L-serine-III. All three polymorphs are orthorhombic, P2(1)2(1)2(1), and feature chains of serine molec...

The structures of two salts of flunarizine, namely 1-bis[(4-fluorophenyl)methyl]-4-[(2E)-3-phenylprop-2-en-1-yl]piperazine, C26H26F2N2, are reported. In flunarizinium nicotinate {systematic name: 4-bis[(4-fluorophenyl)methyl]-1-[(2E)-3-phenylprop-2-en-1-yl]piperazin-1-ium pyridine-3-carboxylate}, C26H27F2N2(+)·C6H4NO2(-), (I), the two ionic components are linked by a short charge-assisted N-H.....

The structural, vibrational, and energetic properties of adducts of alkanes and strong cationic proton donors were studied with composite ab initio calculations. Hydrogen bonding in D-H(+)...H-alkyl adducts contributes to a significant degree to the interactions between the two components, which is substantiated by NBO and AIM results. The hydrogen bonds manifest themselves in the same manner a...