The difficulty in identifying ligands for nuclear hormone receptors remains an obstacle to understanding their function. For example, in the fruit fly Drosophila melanogaster, only one of its nuclear receptors has a known ligand. In this issue of Cell, report that the fruit fly E75 nuclear receptor contains heme in its ligand binding pocket and that the oxidation state of this molecule controls...

Abstract. Single ionization of simple molecules, e.g. H2, CO2, by fast charged particle impact has been studied using a reaction microscope. By measuring the momenta of the emitted electron and the recoil ionic fragment in coincidence, channel-selective low-energy electron spectra have been recorded. The experimental cross sections will be presented, compared with the predictions of state-of-th...

An extended Debye–Hückel theory with fourth order gradient term is developed for electrolyte solutions; namely, the electric potential φ(r) of bulk solution can be described by ∇2φ(r) = κ2φ(r) + LQ2∇4φ(r), where parameters κ and LQ are chosen to reproduce first two roots dielectric response function solution. Three boundary conditions solving problem proposed based upon continuity involving fun...

The concept of quasiresonance was introduced in connection with inelastic collisions between one atom and a vibro-rotationally excited diatomic molecule. In its original form, the collisions induce quasiresonant transfer of energy between the internal degrees of freedom of the diatom: there is a surprisingly accurate low order rational value for the ratio of the changes in the vibrational and r...

We present a simple exact analytical solution, using the Weyl-Titchmarsh-Kodaira spectral theorem, for the spectral function of the one-dimensional diatomic molecule model consisting of two attractive delta function wells in the presence of a static external electric field. For sufficiently deep and far apart wells, this molecule supports both an even and an odd state, and the introduction of a...

Most Eley-Rideal abstraction reactions involve an energetic gas-phase atom reacting directly with a surface adsorbate to form a molecular product. Molecular projectiles are generally less reactive, may dissociate upon collision with the surface, and thus more difficult to prove that they can participate intact in abstraction reactions. Here we provide experimental evidence for direct reactions ...

The shift and broadening of the vibrational frequency of a diatomic molecule adsorbed on a metal surface are calculated on the basis of electromagnetic interactions. Finite molecular size and nonlocal metal response are included in a calculation of the response function, whose pole is the complex normal mode frequency. Finite molecular size is described by a model of a point-like vibrational mo...

The vibrational motion of a molecule is quantized and the resulting energy level spacings give rise to transitions in the mid-IR portion of the electromagnetic spectrum (4000 to ca. 400 cm). As you know from study of the diatomic harmonic oscillator, the energies (or wavenumber positions, cm) of these transitions are related to the bond strength (force constant), bond length, and atomic masses ...

An efficient and accurate analytic gradient method is presented for Hartree-Fock and density functional calculations using multiresolution analysis in multiwavelet bases. The derivative is efficiently computed as an inner product between compressed forms of the density and the differentiated nuclear potential through the Hellmann-Feynman theorem. A smoothed nuclear potential is directly differe...

The recently proposed Partition Theory (PT) (J. Phys. Chem. A 2007, 111, 2229), is illustrated on a simple one-dimensional model of a heteronuclear diatomic molecule. It is shown that a sharp definition for the charge of molecular fragments emerges from PT, and that the ensuing population analysis can be used to study how charge redistributes during dissociation and the implications of that red...