Protein components of the U6 snRNP (Prp24p and LSm2-8) are thought to act cooperatively in facilitating the annealing of U6 and U4 snRNAs during U4/U6 di-snRNP formation. To learn more about the spatial arrangement of these proteins in S. cerevisiae U6 snRNPs, we investigated the structure of this particle by electron microscopy. U6 snRNPs, purified by affinity chromatography and gradient centr...

The two cluster anions, PtMgH3(-) and PtMgH5(-), were studied by photoelectron spectroscopy and theoretical calculations. Experimentally-determined electron affinity (EA) and vertical detachment energy (VDE) values were compared with those predicted by our computations; excellent agreement was found. The calculated structures of PtMgH3(-) and PtMgH3 both exhibit η2-bonded H2 moieties. Activatio...

A series of new conjugated copolymers incorporating the redox-active pyrrolo-TTF unit has been synthesised. The properties of the polymers have been investigated by cyclic voltammetry and electronic absorption spectroscopy, revealing that the pyrrolo-TTF behaves very differently to its thieno-TTF variant. In comparison to thieno analogues, the band gaps of the new polymers are wider than expect...

An overview of the understanding of correlations between energy gap and refractive index of semiconductors is presented here. The atomic approach of Moss, the nearly free electron model of Penn, the oscillator concept of Wemple and the optical polarizability approach of Finkenrath are considered in this study. The Ravindra relation is discussed in the context of alternate approaches that have b...

Spiro-bis-dithiepins are synthesized via dehydrative ring expansion in alpha-hydroxyalkyl spiro-bis-dithianes. Atypical of spiranes possessing axial chirality, the two most stable conformers of substituted spiro-bis-dithiepin have virtually colinear double bonds; i.e., each enantiomer exists in a form of two energy degenerate syn and anti conformations. Because of the high polarizability of the...

We report on differential and integral cross section measurements for the electron impact excitation of the three lowest lying Rydberg bands of electronic states in tetrahydrofuran. The energy range of the present experiments was 15-50 eV with the angular range of the differential cross section measurements being 15°-90°. The important effects of the long-range target dipole moment and the targ...

The energy of Fermi sea perturbed by an external potential is analyzed with the help of an energy anomaly. Using an example of massive Dirac fermions on a circle, we illustrate how the anomaly accounts for the contribution of the deep-lying states. The energy anomaly is a universal function of the applied field and is related to known field-theoretic anomalies. Applied to the transverse polariz...

in this work, we dissect the performance of  two modern perdew-burke-ernzerhof (pbe)-based double-hybrid (dh) density functionals to predict the isotropic and anisotropic polarizabilities of water nanoclusters (h2o)n [n = 2-6]. the considered models include the cubic integrand (ci) and quadratic integrand (qi) functions as well as the spin-opposite-scaled (sos) scheme for perturbative correlati...

It is shown that the charged particles are refracted and reflected on the boundary of field free and laser field regions in vacuum. Simple and transparent estimates are given which show the possibility of channeling of charged and neutral particles having polarizability by strong electromagnetic field of certain laser bunches just as by the field of orientated crystalline planes and axes. These...

The electron-phonon and Coulomb interactions inC60, and larger fullerene spheres are analyzed. The coupling between electrons and intramolecular vibrations give corrections ∼ 1 − 10 meV to the electronic energies for C60, and scales as R −4 in larger molecules. The energies associated with electrostatic interactions are of order ∼ 1 − 4 eV, in C60 and scale as R −1. Charged fullerenes show enha...