Materials Literature
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The [(M+)x[18]crown-6)] supramolecular cations (SC+), in which M+ and [18]crown-6 are alkali metal ions (M+ = Li+, Na+, and Cs+) and 1,4,7,10,13,16-hexaoxacyclooctadecane, respectively, form ionic channel structures through the regular stacks of [18]crown-6 in [Ni(dmit)2]-based molecular conductors (dmit2+ = 2-thioxo-…
We report on the operation of an integrated gated cathode device using a single vertically aligned carbon nanofiber as the field emission element. This device is capable of operation in a moderate vacuum for extended periods of time without experiencing a degradation of performance. Less than 1% of the total emitted c…
Density functional calculations on oxo-manganese complexes of corrole (1) and porphyrin (2 and 3) show a fundamental difference. The ground state of I is the singlet manganese(V) state, 1A(MnV), in which corrole is a closed shell. In contrast, 2 and 3 have high-spin manganese(IV) states, 1A1u and 3A2u respectively. Th…
A novel synthesis is presented of a fourfold ethynyl-substituted perylene diimide dye 4, which acts as a core molecule for the buildup of polyphenylene dendrimers. Around the luminescent core 4, a first-generation (5), a second-generation (6), and a third-generation (7) polyphenylene dendritic environment consisting o…
Supramolecular complex formation imparts stability and substrate selectivity to a simple manganese-porphyrin-based epoxidation catalyst. Lewis acid/Lewis base directed assembly was used to encapsulate the epoxidation catalyst within a supramolecular square structure to form an enzyme-like catalyst system. The “molecul…
The strain dependence of the solution energy of substitutional species is derived by expanding the binary alloy energy with respect to concentration and strain to the second order. Within the approximation of small strain and concentration inhomogeneities, the energy change is found to be proportional to the solute-in…
The orthorhombic rare-earth cobaltate ${\mathrm{Nd}}_{0.67}{\mathrm{Sr}}_{0.33}{\mathrm{CoO}}_{3}$ is studied by neutron powder diffraction. The Co sublattice orders ferromagnetically below ${T}_{c}\ensuremath{\approx}200$ K with the magnetic moments aligned along the c axis. On cooling, ${\mathrm{Nd}}_{0.67}{\mathrm{…
The resistances of individual single-walled carbon nanotubes (SWNTs) are calculated based on Boltzmann transport equation, graphene approximation relation of electronic energy for SWNTs and weak localization (WL) theory. The theoretical results of resistance for SWNTs are compared with experimental measurements. It ha…
The first observation of a magnetic circular x-ray dichroism (MCXD) at the Mn ${L}_{2,3}$ core edges in antiferromagnetic ${\mathrm{LaMnO}}_{3}$ shows canted spin and orbital ( ${m}_{\mathrm{orb}}$) moments arising from lattice distortions. An ${L}_{2,3}$-edge MCXD in ferromagnetic metals and insulators, ${\mathrm{La}…
Abstract Organosoluble polyimides were synthesized with the alicyclic dianhydride 1,8‐dimethylbicyclo[2,2,2]oct‐7‐ene‐2,3,5,6‐tetracarboxylic dianhydride and aromatic diamines. The polyimides possessed good solubility both in strong dipolar solvents and in common solvents; the thermal decomposition temperature of the…
To elucidate the role of amino acid residues adjacent to the catalytic site of pepsin-like enzymes, we analyzed and compared the crystal structures of these enzymes, their complexes with inhibitors, and zymogens in the active site area (a total of 82 structures).In addition to the water molecule (W1) located between t…
Lead zirconate titanate (PZT) films were deposited on nesa silica glass substrates by spin coating using a Pb(NO3)2–Zr(OC3H7n)4–Ti(OC3H7i)4 solution containing polyvinylpyrrolidone and acetylacetone. The coating solution had stable viscosity for over 1300 h at room temperature. Single-layer PZT films as thick as 0.75…
Polymerized carbon nitride nanobells (CNNBs) have been intercalated by a large amount of Li ions using an electrochemical method. Li nanocrystals are observed on the inside surface of CNNB walls, which is direct evidence that a Li nanocrystal can exist at the micropore structure at a heavy intercalating level. Graphen…
We report the perovskite phase stabilization of 0.67Pb(Mg1/3Nb2/3)O3–0.33PbTiO3 (PMN-PT) epitaxial thin films by deposition onto miscut substrates. Films were grown on (001) SrTiO3 substrates with miscut angles from 0 to 8 degrees toward the [100] direction using 90° off-axis magnetron sputtering. Films on high miscut…
A supramolecular complex for investigating the thermodynamic properties of intermolecular aromatic stacking interactions has been developed. The conformation of the complex is locked in a single well-defined conformation by an array of H-bonding interactions that force two aromatic rings on one end of the complex into…
Stabilität und Substratselektivität werden einem einfachen Epoxidierungskatalysator auf Manganporphyrin-Basis durch supramolekulare Komplexbildung verliehen: Hierbei wird der Katalysator in eine supramolekulare quadratische Struktur eingebettet, wodurch ein enzymartiges katalytisches System erhalten wird. Das „molekul…
This work presents the x-ray extended range technique for measuring x-ray mass attenuation coefficients. This technique includes the use of multiple foil attenuators at each energy investigated, allowing independent tests of detector linearity and of the harmonic contributions to the monochromated synchrotron beam. Me…
During plastic deformation of crystalline materials, the collective dynamics of interacting dislocations gives rise to various patterning phenomena. A crucial and still open question is whether the long range dislocation-dislocation interactions which do not have an intrinsic range can lead to spatial patterns which m…
We have used oxygen-plasma-assisted molecular-beam epitaxy (OPA-MBE) to grow CoxTi1−xO2 anatase on SrTiO3(001) for x=∼0.01–0.10, and have measured the structural, compositional, and magnetic properties of the resulting films. Whether epitaxial or polycrystalline, these CoxTi1−xO2 films are ferromagnetic semiconductors…
We demonstrate for the first time the magnetic field distribution of the pure vortex state in lightly doped Mg$_{1-x}$Al$_x$B$_2$ ($x\leq 0.025$) powder samples, by using $^{11}$B NMR in magnetic fields of 23.5 and 47 kOe. The magnetic field distribution at T=5 K is Al-doping dependent, revealing a considerable decrea…