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A high-power high-efficiency laser power transmission system at 100 m based on an optimized multi-cell GaAs converter capable of supplying 9.7 W of electricity is demonstrated. An -testing system integrated with a data acquisition circuit and an analysis software is designed to measure the efficiency and the -characteristics of the laser power converter (LPC). The dependencies of the converter's efficiency with respect to wavelength, laser intensity and temperature are analyzed. A diode laser with 793 nm of wavelength and 24 W of power is used to test the LPC and the software. The maximum efficiency of the LPC is 48.4% at an input laser power of 8 W at room temperature. When the input laser power is 24 W (laser intensity of 60000 W/m 2 ), the efficiency is 40.4% and the output voltage is 4 V. The overall efficiency from electricity to electricity is 11.6%.

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Reactions between [Nb6Cl12(CN)6]4– and [Mn(salen)]+ in MeOH/H2O solvent mixture led to the formation of {[Mn(salen)(H2O)]2[(Mn(salen))2(Nb6Cl12(CN)6)]}·0.66 MeOH·5.33 H2O (1) which has a 2D anionic 4,4′‐network built of [Nb6Cl12(CN)6]4– and [Mn(salen)]+ nodes linked by CN ligands. The layers in 1 stack perfectly on top of each other and generate channels where dimeric complexes [Mn(salen)(H2O)]22+ are located. Unusual cation‐induced solvent‐mediated structural transformations have been observed when 1 was exposed to solutions of different cations. In contact with (Me4N)Cl in MeOH, 1 is transformed to the 2D framework of the previously reported compound [Me4N]2[(Mn(salen))2(Nb6Cl12(CN)6)] (2). In the presence of (Et3BzN)+, 1 is transformed into a mixture of [Et3BzN]2[(Mn(salen)(MeOH))2(Nb6Cl12(CN)6)]·4 MeOH (3) and [Et3BzN]2[(Mn(salen))2 (Nb6Cl12(CN)6)]·3 H2O (4) which are formed as crystals suitable for single‐crystal X‐ray diffraction. Compound 3 consists of heterotrimeric supramolecular anions built of [Nb6Cl12(CN)6]4– linked to two [Mn(salen)(H2O)]+ through two CN ligands located in axial positions, while 4 features 2D anionic 4,4′‐net with the same connectivity as that observed for 1 and 2 but different layer stacking and interlayer spacing. In contact with methanolic solution of (Et4N)+, 1 is converted to [Et4N]2[(Mn(salen)(H2O))2(Nb6Cl12(CN)6)]·6 H2O (5) which is built of heterotrimeric structural motif similar to those found in 3. In the presence of M+ [M+ = Li+, Na+, K+, (Bu4N)+, or (PPh4)+], the 2D framework of 1 is transformed to heteropentamers built of [Nb6Cl12(CN)6]4– linked to four [Mn(salen)(MeOH)]+: [(Mn(salen)(MeOH))4(Nb6Cl12(CN)6)]·4 MeOH (6). The mechanism for these unusual solvent‐mediated phase‐to‐phase transformation is discussed.(© Wiley‐VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2008)

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Polymers undergo severe low-dimensionality effects when they are confined to ultrathin films since most of the structural and dynamical processes involving polymer molecules are correlated to length scales of the order of nanometers. However, the real influence of the size limitation over such processes is often hard to identify as it is masked by interfacial effects. We present the fabrication of a new type of nanostructure consisting of poly[[9-(1-octylnonyl)-9H-carbazole-2,7-diyl]-2,5-thiophenediyl-2,1,3-benzothiadiazole-4,7-diyl-2,5-thiophenediyl] (PCDTBT) thin film that is held up exclusively over tips of poly(ether-ether-ketone) (PEEK) nanopillars. The fabrication method exploits the nonwetting behavior of PCDTBT onto an ordered PEEK nanopillar array when the mobility of the PCDTBT molecules is enhanced by a solvent annealing process. We use this new configuration to characterize the mechanical behavior of free-standing thin film regions, thus in the absence of underlaying substrate, by means of an atomic force microscope (AFM) setup. First, we study how the finite thickness and/or the presence of the underlying substrate influences the mechanical modulus of the material in the linear elastic regime. Moreover, we analyze deep indentations up to the rupture of the thin film, which allow for the measurement of important mechanical features of the nanoconfined polymer, such as its yield strain, the rupture strain, the bending rigidity, etc., which are impossible to investigate in thin films deposited on substrates.

tridentate fashion to each metal center. These complexes, however, posses considerable rotational flexibility about the central eHTP methylene bridge giving rise to a number of low energy rotational conformations. The various conformations of these systems have been probed by X-ray crystallography, N M R spectroscopy, and VDW energy calculations. Although the VDW energy calculations are quite crude, they provide an excellent qualitative road map to the conformations accessible to these systems and provide considerable insight into understanding the structural differences between the Ni and Pd/Pt complexes.The rotational flexibility of these systems could be extremely important in allowing the metals to access one another for cooperative bimetallic behavior. One reaction that is potentially well suited to binuclear systems is hydroformylation and there have been several reports on the effects of homo-and heterobimetallic homogeneous catalysts on the rate and selectivity of hydroformylation rea~tions.'~.'' We are, therefore, particularly interested in studying the hydroformylation activity of bimetallic complexes based on our considerably less sterically hindered binucleating tetraphosphine ligand system (Et2PCH2CH2)(Ph)-PCH,P(Ph)(CH2CH2PEt2), eLTTP.'8-20 This ligand has essentially the same bridging/chelating coordinating properties as eHTP, yet will readily allow two square-planar metal centers to come into close proximity. Indeed, it is in large part these conformational studies on eHTP complexes of the group 10 metals that lead to the design and synthesis of the eLTTP ligand system. Acknowledgment. We thank the National Science Foundation (Grants CHE-86-13089 and CHE-88-23041) for research support and Dr. Frank R. Fronczek (LSU) for collecting the X-ray data on the palladium system. We also acknowledge the helpful comments of the manuscript reviewers. Supplementary Material Available: A stereopair figure of the SYBYL least-squares overlapped structures of Ni2C12(HTP)2+ and Pd2CI2-(HTP)2+, the IH NMR spectra of 2a in CD30H, CD3CN, and CD2CI2, and Tables S-I-S-IV of crystal and data collection parameters and anisotropic thermal parameters (IO pages); Tables S-V and S-VI of observed and calculated structure factors (33 pages). Ordering information is given on any current masthead page. (16) Sanger, A. R. Homogeneous Catalysis with Metal Phosphine Complexes; Pignolet, L. H., Ed.; Plenum: New YorkHead-to-tail carbon disulfide dimers of composition M(C2S4)(C2H4)(PMe,), (M = Mo (3), W (4)) have been prepared by action of CS2 on the ethylene complexes P U~~-M ( C~H , )~( P M~, )~ (M = Mo ( l ) , W (2)). An X-ray analysis, carried out on complex 3, shows the C2S4 unit is acting formally as a four-electron donor ligand, $-bonded to the metal through one of the carbon and two of the sulfur atoms. The complex is monoclinic, C2/c, with a = 26.633 (7) A, b = 8.615 (4) A, c = 19.903 (6) A, j 3 = 103.51 ( 2 ) O , and D(calcd) = 1.60 g cm-, for Z = 8 and R(FJ = 0.048. The analogous reactions of 1 and 2 with SCNPh provide relate...