We have constructed a group of classical potentials based on ab initio density-functional theory (DFT) calculations to describe the chemical bonding between benzenedithiolate (BDT) molecule and gold atoms, including bond stretching, bond angle bending, and dihedral angle torsion involved at the interface between the molecule and gold clusters. Three DFT functionals, local-density approximation ...

Photo-oxidative stability of a series of most common red acrylic paints has been investigated. The paints in question were carmine, quinacridone scarlet, alizarin crimson, brilliant red, vermilion and cadmium red hue. Structural changes, discoloration and weight loss of paints film subjected to UV irradiation in an accelerated ageing chamber were measured using FT-IR spectroscopy, colorimetry a...

Hydrogen bonds are weak, generally intermolecular bonds, which hold much of soft matter together as well as the condensed phases of water, network liquids, and many ferroelectric crystals. The small mass of hydrogen means that they are inherently quantum mechanical in nature, and effects such as zero-point motion and tunneling must be considered, though all too often these effects are not consi...

Stereo-selectively synthesized 1,3-poly-alcohols are introduced as low-dimensional spectroscopic model systems for molecular dynamics in hydrogen-bonded networks. The molecular and vibrational structures of the artificial networks are studied by means of density functional theory. The flexibility of the networks and the time scales associated with hydrogen-bond breakage and formation are invest...

The structures and the OOO and MOO bonding characters of a series of reported side-on ( 2) 1:1 metal complexes of O2 are analyzed by using density functional theory calculations. Comparison of the calculated and experimental systems with respect to OOO bond distance, OOO stretching frequency, and OOO and MOO bond orders provides new insights into subtle influences relevant to O2 activation proc...

The phosphate group of the ADP-insensitive phosphoenzyme (E2-P) of sarcoplasmic reticulum Ca2+ -ATPase (SERCA1a) was studied with infrared spectroscopy to understand the high hydrolysis rate of E2-P. By monitoring an autocatalyzed isotope exchange reaction, three stretching vibrations of the transiently bound phosphate group were selectively observed against a background of 50,000 protein vibra...

The specific-heat difference between the O:H van der Waals bond and the H-O polar-covalent bond and the Coulomb repulsion between electron pairs on adjacent oxygen atoms determine the angle-length-stiffness relaxation dynamics of the hydrogen bond (O:H-O), which is responsible for the density and phonon-stiffness oscillation of water ice over the full temperature range. Cooling shortens and sti...

Various ab initio calculations using the density-functional (DFT), the second order Möller-Plesset perturbation (MP2) and self-consistent reaction field (SCRF) theories were performed on thirteen theoretically possible inositol stereoisomers. Gas phase calculations reveal that the myo- and neo-isomers of inositol (bearing one and two axial hydroxyl groups, respectively) are marginally more stab...

In this study, the structural and optical properties of Al Mg doped zinc oxide Zn0.98M0.02O (M= Al, Mg) prepared by solid state reaction method is investigated. X-ray diffraction (XRD), Scanning Electron Microscopy (SEM), UV-Visible spectroscopy (UV–Vis) Fourier Transform Infrared (FTIR) were employed to study properties. With XRD analysis, it was revealed that all samples are hexagonal wurtzit...

Compared to ethylene and its nonfluorinated derivatives, C(2)F(4) is peculiar in many reactions. It very easily adds to radicals and prefers formation of four-membered rings over Diels-Alder reactions. This has been rationalized by the preference of fluorine for carbon sp(3) hybridization, which is possible on opening of the double bond. Another property, the thermal dissociation of the C ═ C b...