We report on density-functional total-energy calculations of the step formation and interaction energies for vicinal TaC~001! surfaces. Our calculations show that doubleand triple-height steps are favored over singleheight steps for a given vicinal orientation, which is in agreement with recent experimental observations. We provide a description of steps in terms of atomic displacements and cha...

The von Willebrand factor (VWF) A2 crystal structure has revealed the presence of a rare vicinal disulfide bond between C1669 and C1670, predicted to influence domain unfolding required for proteolysis by ADAMTS13. We prepared VWF A2 domain fragments with (A2-VicCC, residues 1473-1670) and without the vicinal disulfide bond (A2-DeltaCC, residues 1473-1668). Compared with A2-DeltaCC, A2-VicCC ex...

On-axis and vicinal GaN/AlN/6H-SiC structures grown under identical conditions have been studied by x-ray diffraction and transmission electron microscopy to demonstrate the distinctive features of vicinal surface epitaxy (VSE) of nitrides on SiC. In VSE, the epilayers are tilted from the substrate due to the out-of-plane lattice mismatch (Nagai tilts), and the in-plane mismatch strains are mor...

The symmetry-induced magnetic anisotropy due to monoatomic steps at strained Ni films is determined using results of first principles relativistic full-potential linearized augmented plane wave (FLAPW) calculations and an analogy with the Néel model. We show that there is a magnetoelastic anisotropy contribution to the uniaxial magnetic anisotropy energy in the vicinal plane of a stepped surfac...

Quantitative side-chain torsion angle χ(1) determinations of phenylalanine residues in Desulfovibrio vulgaris flavodoxin are carried out using exclusively the correlation between the experimental vicinal coupling constants and theoretically determined Karplus equations. Karplus coefficients for nine vicinal coupling related with the torsion angle χ(1) were calculated using the B3LYP functional ...

An efficient method for the diastereo- and enantioselective construction of vicinal all-carbon quaternary stereocenters through palladium-catalyzed decarboxylative cycloaddition of vinylethylene carbonates with activated Michael acceptors was developed. By using a palladium complex generated in situ from [Pd2(dab)3]⋅CHCl3 and a phosphoramidite ligand as a catalyst under mild reaction conditions...

The co-adsorption of CO and OH on two Pt stepped surfaces vicinal to the (111) orientation has been evaluated by means of density functional theory (DFT) calculations. Focusing on Pt(533) and Pt(221), which contain (100) and (111)-steps, respectively, we find that (111)-steps should be more reactive towards CO oxidation than surfaces containing (100)-steps. The DFT results are compared with ele...

Pentavalent uranium complexes of the formula U(V)X(2)[N(SiMe(3))(2)](3) (X = F(-), Cl(-), Br(-), N(3)(-), NCS(-)) are accessible from the oxidation of U(III)[N(SiMe(3))(2)](3) through two sequential, one-electron oxidation reactions (halides) and substitution through salt metathesis (pseudohalides). Uranium(v) mixed-halides are also synthesized by successive one-electron oxidation reactions.

Hydrosilane-B(C6F5)3 adducts were found to activate zirconocene dihalides and generate ternary catalytic systems possessing moderate to high activity in ethylene polymerization to high density polyethylene (HDPE). The activation efficacy of the adducts increased with increasing hydride donor ability and decreased with steric crowding of the particular hydrosilane used. NMR investigation of the ...

New compounds having two indolizine nuclei in a molecule were prepared in low to moderate yields from the reactions of potassium 2-indolizinethiolates with 1,omega-dihalides such as 1,2-diiodoethane, 1,3-dibromopropane, 1,4-dibromobutane, alpha,alpha'-dichloro-o-xylene, and alpha,alpha'-dichloro-p-xylene. Most of the products had the conformation in which the two indolizine rings in the molecul...