The crystal of the title compound, C(6)H(9)N(3)·C(7)H(6)O(2), contains tetra-meric hydrogen-bonded units comprising a central pair of 2-amino-pyrimidine mol-ecules linked across a centre of inversion by N-H⋯N hydrogen bonds and two pendant benzoic acid mol-ecules attached through N-H⋯O and O-H⋯N hydrogen bonds. These hydrogen-bonded units are arranged into layers in (002).

Benchmark quality structures and interaction energies have been produced using explicitly correlated coupled cluster methods for a systematic series of hydrogen and halogen bonded complexes: B···HCCH, B···HCl and B···ClF, with six different Lewis bases B. Excellent agreement with experimental structures is observed, verifying the method used to deduce the equilibrium deviation from collinearity...

Ordered porous solid-state architectures constructed via non-covalent supramolecular self-assembly have attracted increasing interest due to their unique advantages and potential applications. Porous metal-coordination organic frameworks (MOFs) are generated by the assembly of metal coordination centers and organic linkers. Compared to MOFs, porous hydrogen-bonded organic frameworks (HOFs) are ...

In the framework of the one-component model for hydrogen-bonded chains developed by Zolotaryuk and Pnevmatikos [Phys. Lett. A 143 (1990) 233], we study analytically and numerically breather excitations in the continuum and the discrete-carrier limits. We demonstrate that the breathers show high-stability properties especially in the case when the on-site potential is symmetric. We also consider...

The Cu(II) atom in the title compound, [Cu(NO(3))(2)(C(20)H(40)N(4))], is N,N',N'',N'''-chelated by the macrocyclic ligand: the four N atoms form a square, above and below which are located the O atoms of the nitrate ions. The metal atom exists in a tetra-gonally distorted octa-hedron, on a special position of [Formula: see text] site symmetry. One of the amino groups is hydrogen bonded to an O...

2-Methoxyalkanols exhibit interesting variations with regard to equilibrium species of non hydrogen bonded, intramolecular hydrogen bonded and intermolecular hydrogen bonded forms [1-9]. 2-Methoxyethanol in particular has been found to behave as an anion as well as a bidentate ligand in its metal complexes [10-14], Trimethylsiloxyalkanols, Me3SiO(CH2)nOH synthesized through a simple way, are a ...

1. The action of mescaline sulphate on the hydrogen-bonded structure of the RNA constituent of ribosomes of goat brain-cortex slices was studied by using the hyperchromic effect of heating and formaldehyde reaction. 2. The ribosomal total RNA species of the mescaline-treated brain-cortex slices have a smaller proportion of hydrogen-bonded structure than the ribosomal RNA species of the untreate...

The total interaction energies of altogether 15 hydrogen-bonded nucleic acid base pairs containing unusual base tautomers were calculated. The geometry properties of all selected adenine-thymine and guanine-cytosine hydrogen-bonded base pairs enable their incorporation into DNA. Unusual base pairing patterns were compared with Watson-Crick H-bonded structures of the adenine-thymine and guanine-...

Vibrational sum-frequency generation (vSFG) measurements in the frequency and time domains reveal that the interfacial hydrogen bonded OH stretch at the water/calcium fluoride interface is composed of two populations oriented oppositely. The time-resolved vSFG free-induction decay suggested that, whereas the strongly hydrogen bonded OH vibrational stretches, centered near 3140 ± 11 cm-1, are or...