The title new diquinaldine derivative, C27H24N4, forms molecular assemblies organized by intermolecular quinoline pi-pi stacking [3.356 (3) and 3.440 (3) A] and both inter- and intramolecular N-H...N hydrogen bonds [3.039 (3)-3.104 (3) A and 129 (2)-172 (2) degrees]. The combination of such interactions provides readily definable contacts that propagate along each crystallographic axis.

In the title compound, C(4)H(5)N(3)S, the tdihydrothiazole ring is almost planar, the maximum and minimum deviations being 0.188 (2) Å and 0.042 (3) Å, respectively. The crystal structure involves intermolecular N-H⋯N hydrogen bonds.

In the title compound, C(11)H(17)N(2)O(+)·Cl(-), the dihedral angle between the benzene ring and the basal plane of piperazine ring is 39.20 (8)°. In the crystal, intermolecular N-H⋯Cl hydrogen bonds occur. There is also a C-H⋯π inter-action between the benzene rings.

We present a first principles theoretical study of vibrational spectral diffusion and hydrogen bond dynamics in liquid methanol at room temperature. The dynamics of spectral diffusion of OD modes of deuterated methanol reveals two times scales: a short time scale of about 120 fs and a longer time scale of about 3.2 ps. A damped oscillation is also found at around 120–180 fs. Calculations of pow...

The nature of the intermolecular forces between water molecules is the same in small hydrogen-bonded clusters as in the bulk. The rotational spectra of the clusters therefore give insight into the intermolecular forces present in liquid water and ice. The water hexamer is the smallest water cluster to support low-energy structures with branched three-dimensional hydrogen-bond networks, rather t...

In the title organic-inorganic hybrid salt, (C(11)H(20)N(9))[CdCl(5)]·H(2)O, the crystal structure is stabilized by intermolecular hydrogen bonds between the organic cation, the complex inorganic anion and the uncoordinated water molecule, forming a three-dimensional network.

In the title compound, C(11)H(15)N(3)O(3), one of the methyl groups attached to the benzamide unit is slightly twisted with a C-N-C-C torsion angle of 4.04 (13)°. The crystal packing is stabilized by weak intermolecular C-H⋯O hydrogen bonds together with a weak C-H⋯π inter-action.

The title compound, C(15)H(13)N(3)O(8), comprises two crystallographically independent mol-ecules in the asymmetric unit. In the crystal, intermolecular C-H⋯O hydrogen bonds link the molecules and short C=O⋯π contacts are seen.

In the title compound, C(22)H(19)Cl(2)N(5)S, the thia-zole and pyrimidine rings are almost co-planar, making a dihedral angle of 6.48 (7)°. In the crystal, intermolecular N-H⋯N hydrogen bonds link pairs of molecules into centrosymmetric dimers..