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The inclusive single and double differential cross-sections for neutral and charged current processes with four-momentum transfer squared É ¾ between ½½¼ and ¿¼ ¼¼¼ Î ¾ and with Bjorken Ü between ¼¼¼¿¾ and ¼ are measured in · Ô collisions. The data were taken with the H1 detector at HERA between 1994 and 1997, and they correspond to an integrated luminosity(More)
The alkylation of benzene by ethene over H-ZSM-5 is analyzed by means of a hybrid MP2:DFT scheme. Density functional calculations applying periodic boundary conditions (PBE functional) are combined with MP2 energy calculations on a series of cluster models of increasing size which allows extrapolation to the periodic MP2 limit. Basis set truncation errors(More)
Advances in theory and algorithms for electronic structure calculations must be incorporated into program packages to enable them to become routinely used by the broader chemical community. This work reviews advances made over the past five years or so that constitute the major improvements contained in a new release of the Q-Chem quantum chemistry package,(More)
A combination of interpolation methods and local saddle-point search algorithms is probably the most efficient way of finding transition states in chemical reactions. Interpolation methods such as the growing-string method and the nudged-elastic band are able to find an approximation to the minimum-energy pathway and thereby provide a good initial guess for(More)
The kinetics of alkane cracking in zeolites MFI and FAU have been simulated theoretically from first principles. The apparent rate coefficient for alkane cracking was described as the product of the number of alkane molecules per unit mass of zeolite that are close enough to a Brønsted-acid site to be in the reactant state for the cleavage of a specific CC(More)
The influence of flexible walls on the self-diffusion of CH4 in an isolated single walled carbon nanotube, as an example, is studied by molecular dynamics simulations. By simulating the carbon nanotube as a flexible framework we demonstrate that the flexibility has a crucial influence on self-diffusion at low loadings. We show how this influence can be(More)
Ultrathin porous materials, such as zeolite nanosheets, are prominent candidates for performing cataly-sis, drug supply, and separation processes [1, 2] in a highly efficient manner due to exceptionally short transport paths. Predictive design of such processes requires the application of diffusion equations that were derived for macroscopic, homogeneous(More)
Deep-inelastic positron-proton interactions at low values of Bjorken-x down to x ≈ 4 · 10 −5 which give rise to high transverse momentum π •-mesons are studied with the H1 experiment at HERA. The inclusive cross section for π •-mesons produced at small angles with respect to the proton remnant (the forward region) is presented as a function of the(More)