@article{KrausAschenbrennerKlamrothetal.2009,
  author    = {Kraus, Florian and Aschenbrenner, J{\"u}rgen C. and Klamroth, Tillmann and Korber, Nikolaus},
  title     = {Hydrogen polyphosphides P3H23- and P3H32- : synthesis and crystal structure of K3(P3H2)·2.3NH3, Rb3(P3H2)·NH3, [Rb(18-crown-6)]2(P3H3)·7.5NH3, and [Cs(18-crown-6)]2(P3H3)·7NH3},
  issn      = {0020-1669},
  doi       = {10.1021/Ic8014546},
  year      = {2009},
  abstract  = {The incongruous solvation of polyphosphides and phosphanes or the direct reduction of white phosphorus in liquid ammonia leads to the hydrogen polyphosphides catena-dihydrogen triphosphide, P3H23-, and catena-trihydrogen triphosphide, P3H32-, in the crystalline compounds K-3(P3H2)center dot 2.3NH(3) (1), Rb-3(P3H2)center dot NH3 (2), [Rb(18-crown-6)](2)(P3H3)center dot 7.5NH(3) (3), and [Cs(18-crown-6)](2)(P3H3)center dot 7NH(3) (4).},
  language  = {en}
}
@article{KlamrothNest2009,
  author    = {Klamroth, Tillmann and Nest, Mathias},
  title     = {Ultrafast electronic excitations of small sodium clusters and the onset of electron thermalization},
  issn      = {1463-9076},
  doi       = {10.1039/B813619j},
  year      = {2009},
  abstract  = {In this paper we report simulations of the ultrafast laser excitation and relaxation of the correlated valence electrons of a Na-8 cluster. The aim is twofold: first, while the total energy stays constant when the exciting laser pulse is over, we observe that the entropy computed from the reduced one electron density matrix rises on a much longer time scale. We discuss whether this can be understood as the onset of the thermalization of a finite system. Second, we describe this process with eight different methods of wavefunction-based electronic structure theory, which have been adapted for an explicitly time-dependent description. Their respective advantages and limitations for the simulation of the excitation and subsequent relaxation are explained.},
  language  = {en}
}
@article{KlinkuschKlamrothSaalfrank2009,
  author    = {Klinkusch, Stefan and Klamroth, Tillmann and Saalfrank, Peter},
  title     = {Long-range intermolecular charge transfer induced by laser pulses : an explicitly time-dependent configuration interaction approach},
  issn      = {1463-9076},
  doi       = {10.1039/B817873a},
  year      = {2009},
  abstract  = {In this paper, we report simulations of laser-driven many-electron dynamics by means of the time-dependent configuration interaction singles (TD-CIS) approach. The method is capable of describing explicitly time-dependent phenomena beyond perturbation theory and is systematically improvable. In contrast to most time-dependent density functional methods it also allows us to treat long-range charge-transfer states properly. As an example, the laser-pulse induced charge transfer between a donor (ethylene) and an acceptor molecule (tetracyanoethylene, TCNE) is studied by means of TD-CIS. Also, larger aggregates consisting of several donors and/or acceptors are considered. It is shown that the charge distribution and hence the dipole moments of the systems under study are switchable by (a series of) laser pulses which induce selective, state-to-state electronic transitions.},
  language  = {en}
}
@article{KlinkuschSaalfrankKlamroth2009,
  author    = {Klinkusch, Stefan and Saalfrank, Peter and Klamroth, Tillmann},
  title     = {Laser-induced electron dynamics including photoionization : a heuristic model within time-dependent configuration interaction theory},
  issn      = {0021-9606},
  doi       = {10.1063/1.3218847},
  year      = {2009},
  abstract  = {We report simulations of laser-pulse driven many-electron dynamics by means of a simple, heuristic extension of the time-dependent configuration interaction singles (TD-CIS) approach. The extension allows for the treatment of ionizing states as nonstationary states with a finite, energy-dependent lifetime to account for above-threshold ionization losses in laser-driven many-electron dynamics. The extended TD-CIS method is applied to the following specific examples: (i) state-to-state transitions in the LiCN molecule which correspond to intramolecular charge transfer, (ii) creation of electronic wave packets in LiCN including wave packet analysis by pump-probe spectroscopy, and, finally, (iii) the effect of ionization on the dynamic polarizability of H-2 when calculated nonperturbatively by TD-CIS.},
  language  = {en}
}
@article{NacciFoelschZenichowskietal.2009,
  author    = {Nacci, Christophe and Foelsch, Stefan and Zenichowski, Karl and Dokic, Jadranka and Klamroth, Tillmann and Saalfrank, Peter},
  title     = {Current versus temperature-induced switching in a single-molecule tunnel junction : 1,5 cyclooctadiene on Si(001)},
  issn      = {1530-6984},
  doi       = {10.1021/Nl901419g},
  year      = {2009},
  abstract  = {The biconformational switching of single cyclooctadiene molecules chemisorbed on a Si(001) surface was explored by quantum chemical and quantum dynamical calculations and low-temperature scanning tunneling microscopy experiments. The calculations rationalize the experimentally observed switching driven by inelastic electron tunneling (IET) at 5 K. At higher temperatures, they predict a controllable crossover behavior between IET-driven and thermally activated switching, which is fully confirmed by experiment.},
  language  = {en}
}
@article{VazhappillyKlamrothSaalfranketal.2009,
  author    = {Vazhappilly, Tijo and Klamroth, Tillmann and Saalfrank, Peter and Hernandez, Rigoberto},
  title     = {Femtosecond-laser desorption of H-2 (D-2) from Ru(0001) : quantum and classical approaches},
  issn      = {1932-7447},
  doi       = {10.1021/Jp810709k},
  year      = {2009},
  abstract  = {The femtosecond-laser-induced, substrate-mediated associative desorption of molecular hydrogen and deuterium from a Ru(0001) surface in the so-called DIMET limit is studied theoretically. Two widely used models, a "quantum nonadiabatic" approach and a "classical adiabatic" one are employed and compared to each other. The quantum model is realized by the Monte Carlo wave packet (MCWP) method in the framework of open-system density matrix theory: The classical approach is realized with the help of (frictional) Langevin dynamics with stochastic forces. For both models the same ground-state potential energy surface is used and the same two-temperature model adopted to describe the hot- electron-driven desorption dynamics. Apart from these common features both models are different. Still, both account well for the main experimental findings (Wagner et al. Phys. Rev. B 2005, 72, 205404). In particular, an isotope effect in desorption probabilities, the energy content of the desorbing molecules, and the scaling of these observables with laser fluence are reproduced and explained. The similarity of the results obtained with both models is traced back to the fact that, in the present case, the photodynamics takes place dominantly in the ground electronic state because the electronically excited state is rapidly quenched. The short lifetime of the excited state has also the effect that photoreaction cross sections are typically very small. An IR+vis hybrid scheme, by which the adsorbate is vibrationally excited by IR photons prior to the heating of metal electrons with the vis pulse, is shown to successfully promote the reaction even for strongly coupled adsorbate-surface systems.},
  language  = {en}
}