Room-Temperature Spin-Dependent Transport in Metalloporphyrin-Based Supramolecular Wires.

Here we present room-temperature spin-dependent charge transport measurements in single-molecule junctions made of metalloporphyrin-based supramolecular assemblies. They display large conductance switching for magnetoresistance in a single-molecule junction. The magnetoresistance depends acutely on the probed electron pathway through the supramolecular wire: those involving the metal center showed marked magnetoresistance effects as opposed to those exclusively involving the porphyrin ring which present nearly complete absence of spin-dependent charge transport.

Effects of inorganic copper injection in beef cows at late gestation on fetal and postnatal growth, hematology and immune function of their progeny.

To determine if Cu injection during late gestation can affect fetal and postnatal growth, hematology and immune function of progeny, 70 multiparous pregnant Angus cows, at 219 ± 15 d of gestation, were ranked by BW and BCS and randomly assigned to one of two treatments: Cu + (n = 35) in total 160 mg of Cu were administered subcutaneously in two moments (80 mg per moment) at 64 ± 15 d and 54 ± 15 d prepartum; and Cu- (n = 35), in total of 16 ml of sterile NaCl solution (9 g / l) were administered subcutaneously in two moments (8 ml per moment) at 64 ± 15 d and 54 ± 15 d prepartum. Calves from both treatments were weaned at 260 ± 15 d of age, male calves were separated from female calves and stockered on natural pastures until 690 ± 15 d of age, then placed into a feedlot for 104 d before slaughter. At the beginning of the experiment, cows Cu serum concentration was similar (P = 0.

Room temperature conductance switching in a molecular iron(iii) spin crossover junction.

Herein, we report the first room temperature switchable Fe(iii) molecular spin crossover (SCO) tunnel junction. The junction is constructed from [Fe(qsal-I)]NTf (qsal-I = 4-iodo-2-[(8-quinolylimino)methyl]phenolate) molecules self-assembled on graphene surfaces with conductance switching of one order of magnitude associated with the high and low spin states of the SCO complex. Normalized conductance analysis of the current-voltage characteristics as a function of temperature reveals that charge transport across the SCO molecule is dominated by coherent tunnelling.

Tuning Single-Molecule Conductance in Metalloporphyrin-Based Wires via Supramolecular Interactions.

Nature has developed supramolecular constructs to deliver outstanding charge-transport capabilities using metalloporphyrin-based supramolecular arrays. Herein we incorporate simple, naturally inspired supramolecular interactions via the axial complexation of metalloporphyrins into the formation of a single-molecule wire in a nanoscale gap. Small structural changes in the axial coordinating linkers result in dramatic changes in the transport properties of the metalloporphyrin-based wire.

Metal-Organic Nanocapsules with Functionalized s-Heptazine Ligands.

A metalloorganic capsule was synthesized where the ligand is a derivative of heptazine with three carboxylic groups that are coordinated to Cu cations, forming paddle-wheel motifs. Each nanocapsule is neutral, with 12 Cu centers and 8 ligands adopting a rhombicuboctahedron shape. It has almost 3 nm diameter, and the main intermolecular interactions in the solid are π··· π stacking between the CN heptazine moieties.

Effects of inorganic selenium injection on the performance of beef cows and their subsequent calves.

Sixty-seven pregnant Angus cows and their subsequent calves were used in a randomized design to evaluate the effect of inorganic Se injection from 80 d of gestation until weaning on cow reproductive parameters, BW and BCS evolution, milk yield and quality, calf growth and calf hematology parameters. The treatments were as follows: 1) Se+: cows were administered Se as sodium selenite at doses of 0.05 mg/Kg of BW at 80, 140, 200, 260 d of gestation and 30, 90, 150 and 240 d of lactation.

Element-Selective Molecular Charge Transport Characteristics of Binuclear Copper(II)-Lanthanide(III) Complexes.

A series of isostructural dinuclear 3d-4f complexes, isolated as [CuLn(L·SMe)(OOCMe)(NO)]· xMeOH (Ln = Gd 1, Tb 2, Dy 3, and Y 4; x = 0.75-1) and comprising one acetate and two thioether-Schiff base (L·SMe) bridging ligands based on 4-(methylthio)aniline and 2-hydroxy-3-methoxybenzaldehyde (HL·SMe = CHNOS), was synthesized and fully characterized. The magnetic properties of the charge-neutral {CuLn} complexes are dominated by ferromagnetic Cu-Ln exchange interactions.

Magnetic and transport properties of Fe single-molecule magnets: a theoretical insight.

Here, methods of density functional theory (DFT) were employed to study the magnetic and transport properties of a star-shaped single-molecule magnet FeS = 5 complex deposited on a gold surface. The study devoted to the magnetic properties focused on changes in the exchange coupling constants and magnetic anisotropy (zero-field splitting parameters) of the isolated and deposited molecules. Molecule-surface interactions induced significant changes in the antiferromagnetic exchange coupling constants because these depend closely on the geometry of the metal complex.