The chloro-phenyl group of the title compound, C18H12ClNO4, is disordered over two orientations with occupancies of 0.331 (8) and 0.669 (8). An intra-molecular hydrogen bond is formed between a hy-droxy group and the acyclic carbonyl group. In the crystal, molecules are linked into chains along [110] by O-H⋯O and C-H⋯O hydrogen bonds, forming a ladder motif.

The 3D-QSAR CoMSIA technique was applied to a set of 458 peptides binding to the five most widespread HLA-A2-like alleles: A*0201, A*0202, A*0203, A*0206 and A*6802. Models comprising the main physicochemical properties (steric bulk, electron density, hydrophobicity and hydrogen-bond formation abilities) were obtained with acceptable predictivity (q2 ranged from 0.385 to 0.683). The use of coef...

Excitation and emission fluorescence spectra of 2-naphthol and 2-methoxynaphthalene were measured in a series of pure solvents. The spectral shifts are correlated by the Kamlet-Taft parameters (π*, â, and R). As judged from the π* dependence, both molecules have a negligibly small dipole moment in their ground electronic state, which increases in the excited (S1) state. However, the majority of...

The electric field gradient (EFG) has been calculated in zeolite clusters at the aluminium site surrounded by four SiO4 tetrahedra. Density functional theory (DFT) with the 6-31G** basis set has been employed. Formation of a Brønsted acid site by protonation of one oxygen atom of the AlO4 tetrahedron perturbs the coordination of aluminium, i.e., the corresponding Al-O bond is considerably weake...

The relative stability of hydrogen-bonded of Molybdate-Phosphonic Acid (MPA) complex (1:2) ingas phase has been carried out using Density Functional Theory (DFT) methods. The methods are usedfor calculations are B3LYP, BP86 and B3PW91 that have been studied in two series of basis sets: D95**and 6-31+G(d,p) for hydrogen and oxygen atoms; LANL2DZ for Mo and Phosphorus. Predictedhydrogen-bond geom...

The program HBexplore is a new tool for identifying and analyzing hydrogen bonding patterns in biological macromolecules. It selects all potential hydrogen bonds according to geometrical criteria. The hydrogen bond table can then be subjected to further automatic or interactive analysis tools. These tools include the calculation of mean values and distributions of geometrical hydrogen bond para...

A theoretical study of the peri interactions, both intramolecular hydrogen (HB) and chalcogen bonds (YB), in 1-hydroxy-8YH-naphthalene, 1,4-dihydroxy-5,8-di-YH-naphthalene, and 1,5-dihydroxy-4,8-di-YH-naphthalene, with Y = O, S, and Se was carried out. The systems with a OH:Y hydrogen bond are the most stable ones followed by those with a chalcogen O:Y interaction, those with a YH:O hydrogen bo...

First-principles calculations were performed to study the hydrogen bond in the camphorsulfonic (CSA) acid-doped polyaniline system. The density functional theory (DFT) method was used to calculate the ground-state geometric structure optimization. Meanwhile, the electronic excitation energies and corresponding oscillation strengths of the low-lying electronically excited states were investigate...