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  • 1. Andersson, Renée
    et al.
    Kadi, Malin
    Davidsson, Jan
    Hansson, Tony
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Photoionisation of molecular wavepackets – the NaK(C1Σ+) case2002Ingår i: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 352, nr 1-2, s. 106-112Artikel i tidskrift (Refereegranskat)
  • 2.
    Eden, Mattias
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för fysikalisk kemi, oorganisk kemi och strukturkemi.
    Determination of absolute quadrupolar tensor orientations by double-quantum NMR on powders2009Ingår i: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 470, nr 4-6, s. 318-324Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We introduce a new nuclear magnetic resonance (NMR) approach for determining electric field gradient (‘quadrupolar’) tensor orientations directly from polycrystalline powders. It involves a homonuclear 2D experiment that correlates (two-spin) double-quantum and single-quantum coherences of half-integer quadrupolar spin nuclei undergoing magic-angle-spinning. The 2D NMR spectrum is sensitive both to the relative orientations between the correlated quadrupolar tensors and to their orientations relative to the dipolar vector of the spin-pair. A novel strategy to calculate 2D spectra from multi-spin systems is used to extract the tensor orientations. We demonstrate the method by estimating the three 23Na quadrupolar tensor orientations in Na2SO3

  • 3. Eland, J. H. D.
    et al.
    Linusson, Per
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Hedin, L.
    Andersson, E.
    Rubensson, J-E
    Feifel, R.
    Triple ionisation of methane by double Auger and related pathways2010Ingår i: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 485, nr 03-jan, s. 21-25Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Triple ionisation of methane by decay of the singly charged ion with a 1s vacancy produces a trication spectrum starting near 70 eV binding energy. Vibrational excitation in the initial hole state broadens and shifts the triple ionisation bands. Ionisation through core-valence doubly ionised states gives lower triple ionisation onsets and changes the spectral intensity pattern in accordance with retention of the initial valence holes in course of the double Auger effect. The double Auger effects occur both directly and as cascades, the different pathways producing different electron distributions and final state spectra.

  • 4. Eland, J. H. D.
    et al.
    Linusson, Per
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Mucke, M.
    Feifel, R.
    Homonuclear site-specific photochemistry by an ion-electron multi-coincidence spectroscopy technique2012Ingår i: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 548, s. 90-94Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    By combining multi-particle coincidence detection of electrons and ions with ionisation by soft X-ray synchrotron radiation we demonstrate an effective tool for atomic spectroscopy and site-specific photochemistry. Its most novel capability is application to molecular fragmentation after K-shell vacancy production in atoms distinguished only by their chemical environment.

  • 5. Gador, Niklas
    et al.
    Zhang, Bo
    Andersson, Renée
    Johansson, Pia
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Hansson, Tony
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Coherent multichannel nonadiabatic dynamics and parallel excitation pathways in the blue-violet absorption band of Rb22003Ingår i: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 368, nr 1-2, s. 202-208Artikel i tidskrift (Refereegranskat)
  • 6. Gador, Niklas
    et al.
    Zhang, Bo
    Hansson, Tony
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Molecular rotation–vibration coupling by quantum wavepacket interference at potential energy curve crossings2005Ingår i: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 412, nr 4-6, s. 386-390Artikel i tidskrift (Refereegranskat)
  • 7. Gaffney, K. J.
    et al.
    Ji, M.
    Odelius, Michael
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Park, S.
    Sun, Z.
    H-bond switching and ligand exchange dynamics in aqueous ionic solution2011Ingår i: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 504, nr 1-3, s. 1-6Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Aqueous ionic solutions lubricate the chemical machinery of the environment and life. Understanding the impact of ions on the properties of aqueous solutions and how these modified properties influence chemical and conformational dynamics remains an important and elusive objective of physical chemistry research. Here we discuss recent advances in our understanding that have been derived from ultrafast vibrational spectroscopy and molecular dynamics simulations.

  • 8.
    Hedman, Fredrik
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för fysikalisk kemi, oorganisk kemi och strukturkemi.
    Laaksonen, Aatto
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK), Avdelningen för fysikalisk kemi.
    Ewald Summation Based on Nonuniform Fast Fourier Transform2006Ingår i: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 425, nr 1-3, s. 142-147Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We present a novel approach, that combines the traditional Ewald summation technique with the nonuniform Fast Fourier transform to calculate the electrostatic energies and forces in molecular computer simulations. The method can easily be implemented in existing simulation programs. We report here some results from our implementation, where we utilize widely available libraries, and demonstrate the accuracy, and expected computational complexity of our approach.

  • 9. Hu, Guangzhi
    et al.
    Sharifi, Tiva
    Nitze, Florian
    Barzegar, Hamid Reza
    Tai, Cheuk-Wai
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Wagberg, Thomas
    Phase-transfer synthesis of amorphous palladium nanoparticle-functionalized 3D helical carbon nanofibers and its highly catalytic performance towards hydrazine oxidation2012Ingår i: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 543, s. 96-100Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Amorphous palladium nanoparticles functionalized helical carbon nanofibers (ApPd-HCNFs) were synthesized using a phase-transfer method. Palladium nanoparticles (Pd-NP) were first prepared using n-dodecyl sulfide as reducing agent and stabilizing ligands in ethanol. The Pd-NPs were then modified with benzyl mercaptan and transferred into a toluene solution with HCNFs which were decorated with amorphous palladium. The materials were characterized with high-resolution transmission electron microscopy, X-ray diffraction, X-ray photoelectron spectroscopy, energy-dispersive X-ray spectroscopy and cyclic voltammetry showing that amorphous palladium nanoparticles were uniformly anchored at the HCNFs surface and that the ApPd-HCNFs exhibit high electrocatalytic activity towards hydrazine oxidation.

  • 10. Kunnus, K.
    et al.
    Josefsson, Ida
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Schreck, S.
    Quevedo, W.
    Miedema, P. S.
    Techert, S.
    de Groot, F. M. F.
    Föhlisch, A.
    Odelius, Michael
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Wernet, Ph.
    Quantifying covalent interactions with resonant inelastic soft X-ray scattering: Case study of Ni2+ aqua complex2017Ingår i: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 669, s. 196-201Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We analyze the effects of covalent interactions in Ni 2p3d resonant inelastic X-ray scattering (RIXS) spectra from aqueous Ni2+ ions and find that the relative RIXS intensities of ligand-to-metal charge-transfer final states with respect to the ligand-field final states reflect the covalent mixing between Ni 3d and water orbitals. Specifically, the experimental intensity ratio at the Ni L-3-edge allows to determine that the Ni 3d orbitals have on average 5.5% of water character. We propose that 2p3d RIXS at the Ni L-3-edge can be utilized to quantify covalency in Ni complexes without the use of external references or simulations.

  • 11.
    Larsson, Mats
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    McCall, B. J.
    Orel, A. E.
    The dissociative recombination of H-3(+) - a saga coming to an end?2008Ingår i: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 462, nr 06-apr, s. 145-151Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Major progress has been made in the understanding of how H-3(+) recombines with thermal and sub-thermal electrons, a process of great importance to the chemistry of diffuse interstellar clouds. Two independent ion storage ring experiments with rovibrationally cold H-3(+) ions are in excellent agreement, and quantum mechanical calculations agree with the storage ring results quantitatively for the thermal rate constant, if not in all details concerning the cross section. The recombination mechanism is understood. A direct consequence of this progress is that the cosmic-ray ionization rate in diffuse clouds must be shifted upwards to a value larger than 10 (16)s (1). 

  • 12. Mucke, M.
    et al.
    Eland, J. H. D.
    Takahashi, O.
    Linusson, Per
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Lebrun, D.
    Ueda, K.
    Feifel, R.
    Formation and decay of core-orbital vacancies in the water molecule2013Ingår i: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 558, s. 82-87Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Primary steps in the interaction of high energy photons with water creating multiply ionised products are examined experimentally and theoretically. Double Auger decay from a 1s-hole state populates triply ionised states between 80 and 140 eV binding energy. Ejection of one 1s electron and one valence electron gives states around 570 eV which decay to triply ionised states between 75 and 110 eV. Nuclear motion in these states competes with Auger decay and substantially modifies the final state spectra. The double core-hole state from ionisation of both 1s electrons is found at 1171 +/- 1 eV and calculated at 1170.85 eV.

  • 13.
    Nilsson, Anders
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    LaRue, J.
    Öberg, Henrik
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Ogasawara, H.
    Dell'Angela, M.
    Beye, M.
    Öström, Henrik
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Gladh, Jörgen
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Nørskov, J. K.
    Wurth, W.
    Abild-Pedersen, F.
    Pettersson, Lars G. M.
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Catalysis in real time using X-ray lasers2017Ingår i: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 675, s. 145-173Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We describe how the unique temporal and spectral characteristics of X-ray free-electron lasers (XFEL) can be utilized to follow chemical transformations in heterogeneous catalysis in real time. We highlight the systematic study of CO oxidation on Ru(0001), which we initiate either using a femtosecond pulse from an optical laser or by activating only the oxygen atoms using a THz pulse. We find that CO is promoted into an entropy-controlled precursor state prior to desorbing when the surface is heated in the absence of oxygen, whereas in the presence of oxygen, CO desorbs directly into the gas phase. We monitor the activation of atomic oxygen explicitly by the reduced split between bonding and antibonding orbitals as the oxygen comes out of the strongly bound hollow position. Applying these novel XFEL techniques to the full oxidation reaction resulted in the surprising observation of a significant fraction of the reactants at the transition state through the electronic signature of the new bond formation.

  • 14.
    Nordlund, D.
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Ogasawara, H.
    Wernet, Ph.
    Nyberg, M.
    Odelius, M.
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Pettersson, L.G.M.
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Nilsson, A.
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Surface structure of thin ice Ih films2004Ingår i: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 395, nr 1-3, s. 161-165Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    An angular dependent X-ray absorption spectroscopy study of the surface of thin ice films grown on Pt(1 1 1) is presented. Using different probing depths together with spectral calculations based on density functional theory, the spectra are interpreted in terms of the structure of surface, subsurface and bulk regions. It is shown that the crystalline ice is terminated with a large abundance of isotropically distributed free O–H groups and a distorted subsurface.

  • 15. Richardson, V.
    et al.
    Alcaraz, C.
    Geppert, Wolf
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Polášek, M.
    Romanzin, C.
    Sundelin, David
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Thissen, R.
    Tosi, P.
    Žabka, J.
    Ascenzi, D.
    The reactivity of methanimine radical cation (H2CNH.+) and its isomer aminomethylene (HCNH2.+) with methane2021Ingår i: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 775, artikel-id 138611Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Experimental and theoretical studies are presented on the reactions of the isomeric radical cations H2CNH+ and HCNH2+ with CH4. Ionic isomers were generated selectively by VUV dissociative photoionization of azetidine and cyclopropylamine precursors respectively. Both exclusively give H2CNH2+ plus CH3 as products, but differences are observed related to a competition between stripping and complex-mediated H-transfer. Astrochemical implications for Titan’s atmosphere are briefly discussed, where the presence of methanimine (H2CNH), a key prebiotic molecule and a potential precursor for tholins, is proposed on the basis of atmospheric models and the observation of CH2NH2+ ions in Cassini mass spectrometric data.

  • 16. Sanders, Kevin J.
    et al.
    Pell, Andrew J.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Wegner, Sebastian
    Grey, Clare P.
    Pintacuda, Guido
    Broadband MAS NMR spectroscopy in the low-power limit2018Ingår i: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 697, s. 29-37Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We investigate the performance of broadband adiabatic inversion pulses in the high-power (short high-powered adiabatic pulse, SHAP) and low-power (single-sideband-selective adiabatic pulse, S(3)AP) RF regimes on a spin system subjected to large anisotropic interactions. We show by combined experimental results and spin dynamics simulations that when the magic-angle spinning rate exceeds 100 kHz S(3)APs begin outperforming SHAPs. This is especially true for low-gamma nuclei, such as Li-6 in paramagnetic Li-ion battery materials. Finally, we show how S3APs can be improved by combining multiple waveforms sweeping over multiple sidebands simultaneously, in order to produce inverted sideband profiles free from intensity biasing.

  • 17.
    Sarman, Sten
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för fysikalisk kemi, oorganisk kemi och strukturkemi.
    Laaksonen, Aatto
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för fysikalisk kemi, oorganisk kemi och strukturkemi.
    Evaluation of the viscosities of a liquid crystal model system by shear flow simulation2009Ingår i: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 479, nr 1-3, s. 47-51Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The three Miesowicz viscosities of a liquid crystal model system consisting of the Gay-Berne fluid have been obtained by shear flow simulations. The viscosities along an isochore have been followed starting in the nematic phase at high temperatures across the nematic-smectic A phase transition down to low temperatures in the smectic A phase. The relative magnitudes of the viscosities as a function of the structure of the liquid crystal are discussed. The viscosities obtained by the shear flow simulations agree very well with those obtained by Green-Kubo relations in a previous work

  • 18.
    Sarman, Sten
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    Laaksonen, Aatto
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK).
    The temperature dependence of the heat conductivity of a liquid crystal studied by molecular dynamics simulation2010Ingår i: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 485, nr 03-jan, s. 77-82Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    The temperature dependence of the heat conductivity has been obtained for a liquid crystal model based on the Gay-Berne fluid, from the isotropic phase at high temperatures through the nematic phase to the smectic A phase at low temperatures. The ratio of the parallel and the perpendicular components of the heat conductivity is about 2.5:1 in the nematic phase, which is similar to that of real systems. Both Green-Kubo methods and nonequilibrium molecular dynamics methods have been applied and the results agree within in a relative error of a couple of percent, but the latter method is much more efficient.

  • 19.
    Schalk, Oliver
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum. National Research Council of Canada.
    Townsend, Dave
    Wolf, Thomas J. A.
    Holland, David M. P.
    Boguslavskiy, Andrey E.
    Szori, Milan
    Stolow, Albert
    Time-resolved photoelectron spectroscopy of nitrobenzene and its aldehydes2018Ingår i: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 691, s. 379-387Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We report the first femtosecond time-resolved photoelectron spectroscopy study of 2-, 3-and 4-nitrobenzaldehyde (NBA) and nitrobenzene (NBE) in the gas phase upon excitation at 200 nm. In 3- and 4-NBA, the dynamics follow fast intersystem crossing within 1-2 picoseconds. In 2-NBA and NBE, the dynamics are faster (similar to 0.5 ps). 2-NBA undergoes hydrogen transfer similar to solution phase dynamics. NBE either releases NO2 in the excited state or converts internally back to the ground state. We discuss why these channels are suppressed in the other nitrobenzaldehydes.

  • 20.
    Schiros, Theanne
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Haq, Sam
    Ogasawara, Hirohito
    Takahashi, Osamu
    Öström, Henrik
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Andersson, Klas
    Pettersson, Lars G.M.
    Hodgson, Andrew
    Nilsson, Anders
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Structure of water adsorbed on the open Cu(110) surface: H-up, H-down, or both?2006Ingår i: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 429, nr 4-6, s. 415-419Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We investigated the structure of the water monolayer on an open surface, Cu(1 1 0), at low temperature. We found that water adsorbs molecularly, adopting a 2:1 ratio of H-down and H-up configurations. This behavior of water on an open surface is quite different to the behavior on close-packed surfaces, such as Pt(1 1 1) and Ru(0 0 0 1), where water adsorbs primarily H-down, but can be understood on the basis of a range of different water adsorption sites across the observed (7 × 8) unit cell.

  • 21.
    Siegbahn, Per E. M.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för organisk kemi.
    Computational investigations of S-3 structures related to a recent X-ray free electron laser study2017Ingår i: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 690, s. 172-176Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Recent free-electron laser (X-FEL) studies have suggested S-3 states with many features as expected based on previous model calculations and spectroscopy. However, in one of them there is one dramatic surprise. An hydroxide (at the O6 position) on Mn1 was expected, but this group is missing in that X-FEL structure. It has previously been concluded that the hydroxide, which fills the sixth position of the octahedral coordination of Mn1, is necessary to oxidize this manganese to form the S-3 state. In the present study, S-3 structures without the O6 hydroxide have been investigated. Finally, also some S-2 structures were studied.

  • 22.
    Sundelin, David
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Ascenzi, D.
    Richardson, V.
    Alcaraz, C.
    Polášek, M.
    Romanzin, C.
    Thissen, R.
    Tosi, P.
    Žabka, J.
    Geppert, Wolf
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    The reactivity of methanimine radical cation (H2CNH•+) and its isomer aminomethylene (HCNH2•+) with C2H42021Ingår i: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 777, artikel-id 138677Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    Experimental and theoretical studies are presented on the reactivity of H2CNH'+ (methanimine) and HCNH2'+ (aminomethylene) with ethene (C2H4). Selective isomer generation is performed via dissociative photoionization of suitable neutral precursors and reactive cross sections and branching ratios are measured as a function of photon and collision energies. Differences between isomers' reactivity are discussed in light of ab-initio calculations on reaction mechanisms. The main products, for both isomers, are H-elimination, most likely occurring from covalently bound adducts (giving c-CH2CH2CHNH+/CH2NHCHCH2+) and H' atom transfer to yield H2CNH2+. The astrochemical implications of the results are briefly addressed.

  • 23.
    Teymoori, Gholamhasan
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK), Avdelningen för fysikalisk kemi.
    Pahari, Bholanath
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK), Avdelningen för fysikalisk kemi.
    Stevensson, Baltzar
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK), Avdelningen för fysikalisk kemi.
    Edén, Mattias
    Stockholms universitet, Naturvetenskapliga fakulteten, Institutionen för material- och miljökemi (MMK), Avdelningen för fysikalisk kemi.
    Low-power broadband homonuclear dipolar recoupling without decoupling: Double-quantum C-13 NMR correlations at very fast magic-angle spinning2012Ingår i: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 547, s. 103-109Artikel i tidskrift (Refereegranskat)
    Abstract [en]

    We report novel symmetry-based radio-frequency (rf) pulse sequences for efficient excitation of doublequantum (2Q) coherences under very fast (>60 kHz) magic-angle spinning (MAS) conditions. The recursively generated pulse-scheme series, R2(2p)(1)R2(2P)(-1) (p = 1; 2, 3,...), offers broadband C-13-C-13 recoupling in organic solids at a very low rf power. No proton decoupling is required. A high-order average Hamiltonian theory analysis reveals a progressively enhanced resonance-offset compensation for increasing p, as verified both by numerical simulations and 2Q filtration NMR experiments on C-13(2)-glycine, [2,3-C-13(2)] alanine, and [U-C-13] tyrosine at 14.1 T and 66 kHz MAS, where the pulse schemes with p >= 3 compare favorably to current state-of-the-art recoupling options.

  • 24.
    Wang, Dong
    et al.
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Larson, Åsa
    Karlsson, Hans O.
    Hansson, Tony
    Stockholms universitet, Naturvetenskapliga fakulteten, Fysikum.
    Molecular quantum wavepacket revivals in coupled electronic states2007Ingår i: Chemical Physics Letters, ISSN 0009-2614, E-ISSN 1873-4448, Vol. 449, nr 4-6, s. 266-271Artikel i tidskrift (Refereegranskat)
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