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- ItemDicyclohexylbis(naphthalen-1-ylmethyl)phosphonium chloride chloroform disolvate(Chester : International Union of Crystallography, 2012) Gowrisankar, S.; Neumann, H.; Spannenberg, A.; Beller, M.In the title solvated phosphonium salt, C34H40P+·Cl -·2CHCl3, the two cyclohexyl and two 1-naphthylmethyl groups at the P atom are in a distorted tetrahedral arrangement [105.26 (6)-113.35 (6)°]. Both cyclohexyl rings adopt a chair conformation. The dihedral angle between the naphthyl ring systems is 74.08 (3)°.
- ItemDicarbonyl-{3,3′-di-tert-butyl-5,5′-di-methoxy-2, 2′-bis[(4,4,5,5-tetraphenyl-1,3,2-dioxaphospho-lan-2-yl)-oxy-κP] biphen-yl}hydridorhodium(I) diethyl ether monosolvate(Chester : International Union of Crystallography, 2012) Selent, D.; Spannenberg, A.; Börner, A.In the title compound, [Rh(C 74H 68O 8P2)H(CO) 2]·C 4H 10O, the C 2HP 2 coordination set at the Rh I ion is arranged in a distorted trigonal-planar geometry with one P atom of the diphosphite mol-ecule and the H atom adopting the axial coordination sites.
- Item2,4-Bis(diphenyl-phosphan-yl)-1,1,2,3,3,4-hexa-phenyl-1,3-diphospha-2, 4-dibora-cyclo-butane tetra-hydro-furan sesqui-solvate(Chester : International Union of Crystallography, 2012) Peulecke, N.; Müller, B.H.; Spannenberg, A.; Rosenthal, U.In the title compound, C60H50B2P 4·1.5C4H8O, the diphospha-diborane mol-ecule lies on an inversion centre, whereas the disordered tetra-hydro-furan solvent mol-ecule is in a general position with a partial occupancy of 0.75. The diphosphadiborane mol-ecule consists of an ideal planar four-membered B 2P2 ring with an additional phenyl and a-PPH2 group attached to each B atom.
- ItemDi-μ-sulfido-bis{[rac-1,2-bis(η5-4,5,6, 7-tetrahydroinden-1-yl)ethane]zirconium(IV)} toluene monosolvate(Chester : International Union of Crystallography, 2012) Haehnel, M.; Altenburger, K.; Spannenberg, A.; Arndt, P.; Rosenthal, U.The title dimeric zirconium complex, [Zr3(C20H 24)2S2]·C7H8, was obtained from the reaction of (ebthi)Zr(η2-Me3Si-C2-SiMe3) [ebthi is rac-1,2-bis(η5-4,5,6,7-tetrahydroinden-1-yl)ethane] and S=C=N-ada (ada = adamantan-1-yl) along with the formation of the isonitrile C N-ada. Each ZrIV atom is coordinated by the sterically hindered ebthi ligand and two μ-sulfide ligands in a strongly distorted tetrahedral geometry. The [ZrS]2 unit is almost planar (mean deviation from the best plane of the four atoms = 0.025Å). A -CH2-CH2- group in one ebthi ligand was disordered over two sites, with refined occupancy factors of 0.551(6) and 0.449(6). The asymmetric unit also contains a toluene solvent molecule.
- ItemTetracarbonyl[bis(diphenylphosphanyl)-tetramethyldisiloxane- κ 2 P,P′]chromium(0)(Chester : International Union of Crystallography, 2012) Peulecke, N.; Müller, B.H.; Spannenberg, A.; Rosenthal, U.The title compound, [Cr(C 28H 32OP 2Si 2)(CO) 4], was obtained by the ligand-exchange reaction of Cr(CO) 6 with (Ph 2PSiMe 2) 2O in refluxing toluene. The CrC 4P 2 coordination geometry is distorted octa-hedral, with a P - Cr - P bite angle of 99.22 (4)°.
- ItemOberflächenchemie nano- und mikrodimensionaler Materialien und Werkstoffe : Schlussbericht zum Vorhaben ; Laufzeit: 01.09.2008 bis 31.01.2012(Hannover : Technische Informationsbibliothek (TIB), 2012) Rauschenbach, Bernd; Gerlach, Jürgen W.; Hirsch, Dietmar; Mändl, Stephan; Arnold, Th.; Mießler, André; Prager, Lutz; Prager, Andrea; Elsner, Christian; Reichelt, Senta; Pender, Alya[no abstract available]
- ItemComplexity Theory(Zürich : EMS Publ. House, 2012) Goldreich, Oded; Sudan, Madhu; Vadhan, SalilComputational Complexity Theory is the mathematical study of the intrinsic power and limitations of computational resources like time, space, or randomness. The current workshop focused on recent developments in various sub-areas including arithmetic complexity, Boolean complexity, communication complexity, cryptography, probabilistic proof systems, and pseudorandomness. Many of the developments are related to diverse mathematical fields such as algebraic geometry, combinatorial number theory, probability theory, representation theory, and the theory of error-correcting codes.
- ItemA vanishing diffusion limit in a nonstandard system of phase field equations(Berlin : Weierstraß-Institut für Angewandte Analysis und Stochastik, 2012) Colli, Pierluigi; Gilardi, Gianni; Krejci, Pavel; Sprekels, JürgenWe are concerned with a nonstandard phase field model of CahnHilliard type. The model, which was introduced by Podio-Guidugli (Ric. Mat. 2006), describes two-species phase segregation and consists of a system of two highly nonlinearly coupled PDEs. It has been recently investigated by Colli, Gilardi, Podio-Guidugli, and Sprekels in a series of papers: see, in particular, SIAM J. Appl. Math. 2011, and Boll. Unione Mat. Ital. 2012. In the latter contribution, the authors can treat the very general case in which the diffusivity coefficient of the parabolic PDE is allowed to depend nonlinearly on both variables. In the same framework, this paper investigates the asymptotic limit of the solutions to the initial-boundary value problems as the diffusion coefficient ơ in the equation governing the evolution of the order parameter tends to zero. We prove that such a limit actually exists and solves the limit problem, which couples a nonlinear PDE of parabolic type with an ODE accounting for the phase dynamics. In the case of a constant diffusivity, we are able to show uniqueness and to improve the regularity of the solution.
- ItemThe Mathematics and Statistics of Quantitative Risk Management(Zürich : EMS Publ. House, 2012) Embrechts, Paul; Mikosch, ThomasIt was the aim of this workshop to gather a multidisciplinary and international group of scientists at the forefront of research in areas related to the mathematics and statistics of quantitative risk management. The main objectives of this workshop were to break down disciplinary barriers that often limit collaborative research in quantitative risk management, and to communicate the state of the art research from the different disciplines, and to point towards new directions of research.
- ItemSimulation based policy iteration for American style derivatives : a multilevel approach(Berlin : Weierstraß-Institut für Angewandte Analysis und Stochastik, 2012) Belomestny, Denis; Ladkau, Marcel; Schoenmakers, John G.M.This paper presents a novel approach to reduce the complexity of simulation based policy iteration methods for pricing American options. Typically, Monte Carlo construction of an improved policy gives rise to a nested simulation algorithm for the price of the American product. In this respect our new approach uses the multilevel idea in the context of the inner simulations required, where each level corresponds to a specific number of inner simulations. A thorough analysis of the crucial convergence rates in the respective multilevel policy improvement algorithm is presented. A detailed complexity analysis shows that a significant reduction in computational effort can be achieved in comparison to standard Monte Carlo based policy iteration.