[en] The High Flux Beam Reactor at Brookhaven National Laboratory located in Upton, New York, was used in all experiments described in this thesis. Two main types of problems were tackled with this technique: (i) the structures of transition metal hydrido complexes and (ii) the determination of the absolute configuration of chiral CHD groups generated via biochemical processes. Transition metal hydrido complexes have been studies extensively due to several reasons: (i) their potential for catalysis in organic synthetic reactions such as hydrogenation, hydroformulation, and olefin isomerization; (ii) their unconventional bonding mode in metal clusters; and (iii) their potential as hydrogen storage materials. Six transition metal hydride complexes have been studied in this work which fall into this category. The compounds studies include: (i) a transition metal dimer containing bridging hydrides, [(C₅(CH₃)₅Ir)₂ (μ-H)₃]⁺[ClO₄]^-2C₆H₆; (ii) compounds suspected to have agostic hydride interactions, [cis-IrH(OH)(PMe₃)₄]⁺[PF₆]^-, Cp₃U = CHPMe³, and (C₅Me₅)₂Th(μ-CH₂)(μ-1-3,4-Me₂C₅H₂) ZrMe(C₅H₅); (iii) a metal cluster containing face-bridging hydrogen atoms H₆Cu₆[P(p-toyl)₃]₆; and (iv) the complex HRh[P(C₆H₅)₃]₄, in which the shortest hydrogen-metal bond distance (1.31(8)angstrom) was discovered. The appendix section is concerned with the powerful, yet presently under-utilized application of neutron diffraction in the determination of absolute configurations of molecules bearing chiral methylene groups. Here, the systems malate/succinate and acetaldehyde/alcohol have been studied and confirmed to be consistent with previous (non-crystallographic) studies

No abstract available

No abstract available

No abstract available

No abstract available

No abstract available

[en] Plastic microchannel crystallization template designs made from inexpensive cyclic olefin copolymers have been shown to be low-birefringent, X-ray transmissive and compatible with microfluidic fabrication in restricted geometry. The model proteins thaumatin, lysozyme and bacteriorhodopsin demonstrated the feasibility of conducting counter-diffusion equilibration within the new plastic configuration. Crystals of each of these proteins were directly evaluated in situ using synchrotron radiation and their diffraction quality was evaluated without invasive manipulation or cryofreezing. Protein crystals able to produce complete X-ray data sets were used to calculate electron-density maps for structure determination. Fluidic crystallization in the plastic platform was also coupled with a commercialized automated imager and an in situ X-ray scanner that allowed optical and X-ray inspection of crystallization hits. The results demonstrate the feasibility of rapid nanovolume counter-diffusion crystallization experiments without the need for additional instrumentation

[en] We have collected neutron diffraction data on a large single crystal of the title compound. The most surprising result is an extremely short Rh-H distance of 1.31(8) A, presumably caused by steric interactions involving the bulky triphenyl phosphine ligands. Crystallographic details: HRh[P(C₆H₅)₃]₄ . ¹/₂C₆H₆ crystallizes in the space group Pa3, with a = b = c = 22.776(3) A, Z = 8. Data were collected at the Brookhaven High Flux Beam reactor at a temperature of -23⁰C, λ = 1.15882(7) A^-1. Least-squares refinement (in which the phenyl rings were treated as rigid groups) resulted in an R factor [based on data with f > 4σ(F)] of 0.12 for 914 reflections and 95 parameters. 10 refs

No abstract available

No abstract available