The question of how to describe the crossing of molecular electronic states is one of the most challenging issues in contemporary chemical dynamics. In recent years, the fundamental concept of conical intersections (CIs) of electronic potential energy...
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Understanding the hydrated proton is a critically important problem that continues to engage the research efforts of chemists, physicists, and biologists because of its involvement in a wide array of phenomena. Only recently have several unique properties of...
Low-temperature ultrahigh-vacuum scanning tunneling microscopy was employed to analyze the electronic behavior of Au 55 clusters stabilized by [P(C 6 H 5 ) 3 ] 12 Cl 6 ligands. At 7 K, the actual arrangement of the C 6 H 5 rings of the ligand molecules...
We present a mechanism of high-temperature sublimation of carbon nanotubes that does not destroy their ordered makeup even upon significant loss of mass. The atoms depart to the gas phase from the pentagonâheptagon dislocation cores, while the bond...
We performed molecular dynamics simulations of the hydration of Na + and K + in infinitely long single-walled armchair carbon nanotubes (CNTs) at 298 K. Simulation results indicate that the preferential orientation of water molecules in coordination shells...
We study collective vibrational breathing modes in the Raman spectrum of a multiwalled carbon nanotube. In correlation with high-resolution transmission electron microscopy, we find that these modes have energies differing by more than 23% from the radial...
Novel carbon nanotubeâmetal cluster structures are proposed as prototype systems for molecular recognition at the nanoscale. Ab initio calculations show that already the bare nanotube cluster system displays some specificity because the adsorption of...
Metal-atom migration outside from a defective fullerene cage of a metallofullerene Gd@C 82 (Ca@C 82 ), where the Gd 3+ (Ca 2+ ) ion is incorporated inside the C 2 v âC 82 cage, is discussed in detail at the B3LYP DFT level of theory. The metal-atom...
The local electronic structure due to the adsorption of Co on Cu(111) is studied using an embedded cluster model, in which the crystal background is taken into account via an effective density functional theory (DFT)-based potential. This approach goes beyond...
We show by molecular dynamics and first principle calculations that a water chain confined in carbon nanotubes can self-adjust into regular oscillation with remarkably lower entropy from random thermal motion with higher entropy at room temperature. The...
We establish and validate a measurement method based on wrinklingâcracking phenomena that allows unambiguous measurements of three fundamental mechanical properties in nanoscale thin film geometries, including elastic modulus, strength, and fracture strain....
Confinement can induce unusual behavior in the properties of matter. Using molecular dynamics simulations, we show here that water confined to carbon nanotubes of a critical size under ambient conditions (1 bar, 300 K) can undergo a transition into a state...
An âelectrostaticâ eigenmode method based on the coupling of evanescent electric fields is presented for modeling the hybridization of localized surface plasmon resonances in metallic nanoparticles of arbitrary shape. The method yields simple analytical...
Using first principles theory based on density functional formulation we have studied the energetics and thermal stability of storing hydrogen in BâN-based nanostructures. We show that hydrogen molecule enters through the hexagonal face of the B 36 N 36 ...
We perform transmission electron microscopy, electron diffraction, and Raman scattering experiments on an individual suspended double-walled carbon nanotube (DWCNT). The first two techniques allow the unambiguous determination of the DWCNT structure:...
Spin coherence dynamics of semiconductor quantum dots under hydrostatic pressure has been investigated by combining the ultrafast optical orientation method with the diamond-anvil cell technique. Spin confined within quantum dots is observed to be robust up...
We report a first-principles prediction of a new two-dimensional inorganic material, namely, the B 2 C graphene in which the boron and carbon atoms are packed into a mosaic of hexagons and rhombuses. In the B 2 C graphene, each carbon atom is bonded with four...
Substrate and nanotube polarization are shown to qualitatively change a nanotube bandstructure. The effect is studied in a linear approximation in an external potential which causes the changes. A work function difference between the nanotube and gold surface...