The structure and the electronic properties of single-walled zigzag BN and B3C2N3 nanotubes (n, 0; n=4–10) were investigated using first-principles calculations based on a density functional theory. A plane–wave basis set with periodic boundary conditions in conjunction with Vanderbilt ultrasoft pseudo-potential was employed. The energy gap of ZB3C<su...

The structure and the electronic properties of single-walled zigzag BN and B3C2N3 nanotubes (n, 0; n=4–10) were investigated using first-principles calculations based on a density functional theory. A plane–wave basis set with periodic boundary conditions in conjunction with Vanderbilt ultrasoft pseudo-potential was employed. The energy gap of ZB3C<su...

We develop a continuous-time regime-switching model for the term structure of interest rates, in which the spot rate follows the Taylor rule, and government bonds at different maturities are priced by no-arbitrage. We allow the coefficients of the Taylor rule and the dynamics of inflation and output gap to be regime-dependent. We estimate the model using government bond yields and find that the...

We study the effect of an external field on (1 + 1) and (2 + 1) dimensional elastic manifolds, at zero temperature and with random bond disorder. Due to the glassy energy landscape the configuration of a manifold changes often in abrupt, “first order” -type of large jumps when the field is applied. First the scaling behavior of the energy gap between the global energy minimum and the next lowes...

The tight-binding (TB) Hamiltonian is parametrized for Ca nanoclusters by fitting to the energy surfaces of small clusters and to the total energy and band structure of bulk fcc and bcc calcium calculated within an all-electron density-functional formalism. Clusters of 32 to 84 atoms are optimized using the TB model and a combination of molecular dynamics–simulated annealing and genetic algorit...

in this study, the adsorption of 4-hydroxy phenyl-azobenzene on the surface of (4, 0) zigzag open-end boron nitride nanotube (bnnt) has been investigated by quantum calculations. in order to find the preferred adsorption site, different positions and orientations were considered. the impacts of donor-acceptor electron delocalization on the structural and electronic properties and reactivity of ...

Multiconfigurational quantum chemical methods (CASSCF/CASPT2) have been used to study the chemical bond in the actinide diatoms Ac2, Th2, Pa2, and U2. Scalar relativistic effects and spin−orbit coupling have been included in the calculations. In the Ac2 and Th2 diatoms the atomic 6d, 7s, and 7p orbitals are the significant contributors to the bond, while for the two heavier diatoms, the 5f orbi...

Electronic energy (chemical bond energy) is the exclusive source of utilizable energy in biological systems. The release of this energy is mediated enzymically. The energy required to rupture a single covalent or ionic bond is prohibitively high under physiological conditions [in the range of 80-200 kcal/mol (1 kcal = 4.18 kJ)]. By the technique of the pairing of bond rupture (two juxtaposed bo...

We have previously performed empirical valence bond calculations of the kinetic activation barriers, Δ G‡calc, for the deprotonation of complexes between TIM and the whole substrate glyceraldehyde-3-phosphate (GAP, Kulkarni et al. J. Am. Chem. Soc. 2017 , 139 , 10514 - 10525 ). We now extend this work to also study the deprotonation of the substrate pieces glycolaldehyde (GA) and GA·HPi [HPi = ...