Nanometer thick elastic graphene engine.

Significant progress has been made in the construction and theoretical understanding of molecular motors because of their potential use. Here, we have demonstrated fabrication of a simple but powerful 1 nm thick graphene engine. The engine comprises a high elastic membrane-piston made of graphene and weakly chemisorbed ClF3 molecules as the high power volume changeable actuator, while a 532 nm LASER acts as the ignition plug. Rapid volume expansion of the ClF3 molecules leads to graphene blisters. The size of the blister is controllable by changing the ignition parameters. The estimated internal pressure per expansion cycle of the engine is about ∼10(6) Pa. The graphene engine presented here shows exceptional reliability, showing no degradation after 10,000 cycles.

Biodistribution of rhenium cluster complex K4[Re6S8(CN)6] in the body of laboratory rats.

We studied the biodistribution of luminescent octahedral rhenium cluster complex K4[Re6S8(CN)6], a promising agent for photodynamic therapy. It was shown that rhenium complex [Re6S8(CN)6](4-)is mainly accumulated in the liver, the central organ of metabolism, and can be excreted by the kidneys. The cluster complex was also accumulated in the spleen in significant amount, which makes it a promising agent for creation of preparations for diagnostics and treatment of lymphoproliferative disorders. The mean lethal dose of the cluster complex was 0.38 g/kg.

Field emission properties of a graphene/polymer composite.

Thin graphene/polymer sheet composites were fabricated using easily soluble expanded graphite (ESEG), and their field emission (FE) parameters were examined. Due to the high dispersability of ESEG, a stable graphene suspension was prepared by ultrasonication in toluene without the need for a surfactant. The suspension consisted of exfoliated graphene sheets with a thickness of 1 - 2 nm. Using a calendering process, the solution was further shear mixed with ethyl cellulose to obtain a well-dispersed graphene/polymer composite. The composite was screen printed onto a conducing substrate to fabricate the FE cathode layers. The FE measurements were taken in a diode configuration at an applied electrostatic field and inter-electrode distance of 1.7 to 6 V/microm and approximately 200 microm, respectively. The threshold turn-on-field was approximately 3.5 V/microm at a current density of approximately 10 microA/cm2 with a corresponding mean field enhancement factor of 1350 +/- 50. Emission occurred mainly from the edges and bends of the graphene layers. The luminescence uniformity of the composite cathode layers was examined using a phosphor-coated anode.

Electronic Switch in the Carbon-Centered [Re(12)CS(17)(CN)(6)] Nanocluster.

An abrupt change in internuclear Re-Re distances between {Re(6)} subunits in the carbon-centered [Re(12)mu(6)-CS(17)(CN)(6)](n-) complexes caused by the change of the oxidation state (n = 6, 8) is first theoretically shown to be possibly controlled by an external electric field. (13)C NMR signal is shown to change over ~400 ppm (~37G) for mu(6)-C atom together with n. Thereby, the metal cluster [Re(12)mu(6)-CS(17)(CN)(6)](n-) can be considered as a perspective model of a molecular switch.

Unexpected ligand substitutions in the cluster core {Re6Se8}: synthesis and structure of the novel cluster compound Cs11(H3O)[Re6Se4(O)4Cl6]3.4H2O.

The compound Cs11(H3O)[Re6Se4(O)4Cl6]3.4H2O containing a novel cluster core {Re6Se4(O)4} with ordered ligands, where the 4 positions of one face of a Se4(O)4 cube are occupied exclusively by Se atoms and 4 O atoms lie in the opposite face was synthesized via the interaction of solid Re6Se8Br2 with molten KOH.

[[Cu(en)(2)](2)Re(4)Te(4)(CN)(12)].5H(2)O and [[Cu(en)(2)](2)Re(6)Te(8)(CN)(6)].5H(2)O: bonding of a transition-metal complex to a rhenium chalcocyanide cluster.

The use of a cyano group of a transition-metal cluster complex to bond to another transition-metal complex has been realized in the syntheses of [[Cu(en)(2)](2)Re(4)Te(4)(CN)(12)].5H(2)O (1) and [[Cu(en)(2)](2)Re(6)Te(8)(CN)(6)].5H(2)O (2), (en = ethylenediamine). These compounds have been synthesized by the reaction of an aqueous solution of K(4)[Re(4)Te(4)(CN)(12)].5H(2)O (for 1) or K(4)[Re(6)Te(8)(CN)(6)] (for 2) with an ammonia solution of Cu(en)(2)Cl(2). In each compound, two Cu(en)(2) groups are bonded to the Re cluster through Cu-N(cyanide) bonds. In compound 1, which contains a tetrahedral cluster core, the Cu(en)(2) groups are necessarily bonded to cis cyano groups; in compound 2, which has an octahedral cluster core, they are bonded to trans cyano groups. Compound 1 crystallizes in the monoclinic space group C2/c with four formulas in unit cell of dimensions a = 18.9077(10), b = 15.4841(8), c = 14.4483(8) A, beta = 95.124(1) degrees, and V = 4213.1(4) A(3) (T = 153 K); compound 2 crystallizes in the triclinic space group P1 with one formula in a unit cell of dimensions a = 9.4906(3), b = 10.6529(4), c = 12. 6252(5) A, alpha = 113.599(1) degrees, beta = 103.404(1) degrees, gamma = 92.659(1) degrees, and V = 1123.87(7) A(3) (T = 153 K).

Structure of new porous compounds after annealing in vacuum.

Dehydration process in recently synthesized porous inorganic salts formed by large cluster anions [Re6X8(CN)6]4- (X= S, Se), transition metal cations and water molecules has been investigated. Desolvation process of the complex Co(DMF)6[Mo6Br8(NCS)6], where DMF dimethylformamide. has been studied. CoK, MoK and ReL3 XAFS measurements of these new complicated compounds before and after annealing in vacuum at temperature up to 250 degrees C were performed. Changes of electronic and spatial structure of these compounds under the heating process have been established and adequate structural models of the amorphous compounds obtained are suggested and discussed.