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Bin Jiang - One of the best experts on this subject based on the ideXlab platform.
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mode specific and bond selective Dissociative Chemisorption of chd 3 and ch 2 d 2 on ni 111 revisited using a new potential energy surface
Science China-chemistry, 2018Co-Authors: Xueyao Zhou, Bin JiangAbstract:Dissociative Chemisorption of methane on a nickel surface is a prototypical system for studying mode-specific chemistry in gas-surface reactions. We recently developed a fifteen-dimensional potential energy surface for this system which has proven to be chemically accurate in reproducing the measured absolute Dissociative sticking probabilities of CHD 3 in thermal conditions and with vibrational excitation on Ni(111) at high incident energies. Here, using this new potential energy surface, we explored mode specificity and bond selectivity for CHD 3 and CH 2 D 2 Dissociative Chemisorption at low incidence energies down to ~50 kJ/mol via a quasi-classical trajectory method. Our calculated dissociation probabilities are consistent with previous theoretical and experimental ones with an average shift in translational energy of ~8 kJ/mol. Our results very well reproduce the C–H/C–D branching ratio upon the C–H local mode excitation, which can be rationalized by the sudden vector projection model. Quantitatively, however, the calculated Dissociative sticking probabilities are systematically larger than experimental ones, due presumably to the artificial zero point energy leakage into reaction coordinate. Further high-dimensional quantum dynamics calculations are necessary for acquiring a chemically accurate description of methane Dissociative Chemisorption at low incident energies.
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Dissociative Chemisorption of o2 on al 111 dynamics on a correlated wave function based potential energy surface
Journal of Physical Chemistry Letters, 2018Co-Authors: Rongrong Yin, Hua Guo, Yaolong Zhang, Florian Libisch, Emily A Carter, Bin JiangAbstract:Dissociative Chemisorption of O2 on the Al(111) surface represents an extensively studied prototype for understanding the interaction between O2 and metal surfaces. It is well known that the experimentally observed activation barrier for O2 dissociation is not captured by conventional density functional theory. The interpretation of this barrier as a result of spin transitions along the reaction path has been challenged by recent embedded correlated wave function (ECW) calculations that naturally yield an adiabatic barrier. However, the ECW calculations have been limited to a static analysis of the reaction pathways and have not yet been tested by dynamics simulations. We present a global six-dimensional potential energy surface (PES) for this system parametrized with ECW data points. This new PES provides a reasonable description of the site-specific and orientation-dependent activation barriers. Quasi-classical trajectory calculations on this PES semiquantitatively reproduce both the observed translatio...
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Vibrational control of selective bond cleavage in Dissociative Chemisorption of methanol on Cu(111)
Nature Publishing Group, 2018Co-Authors: Jialu Chen, Xueyao Zhou, Yaolong Zhang, Bin JiangAbstract:Dissociative Chemisorption of methanol on metal surfaces is a key step for hydrogen production. Here the authors use quasi-quantized molecular dynamics simulations to alter the branching ratios for methanol Dissociative Chemisorption on Cu(111) via selectively exciting specific vibrational modes
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Dissociative Chemisorption of O2 on Al(111): Dynamics on a Correlated Wave-Function-Based Potential Energy Surface
2018Co-Authors: Rongrong Yin, Hua Guo, Yaolong Zhang, Florian Libisch, Emily A Carter, Bin JiangAbstract:Dissociative Chemisorption of O2 on the Al(111) surface represents an extensively studied prototype for understanding the interaction between O2 and metal surfaces. It is well known that the experimentally observed activation barrier for O2 dissociation is not captured by conventional density functional theory. The interpretation of this barrier as a result of spin transitions along the reaction path has been challenged by recent embedded correlated wave function (ECW) calculations that naturally yield an adiabatic barrier. However, the ECW calculations have been limited to a static analysis of the reaction pathways and have not yet been tested by dynamics simulations. We present a global six-dimensional potential energy surface (PES) for this system parametrized with ECW data points. This new PES provides a reasonable description of the site-specific and orientation-dependent activation barriers. Quasi-classical trajectory calculations on this PES semiquantitatively reproduce both the observed translational energy dependence of the sticking probability and steric effects with aligned O2 molecules
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mode specific electronic friction in Dissociative Chemisorption on metal surfaces h2 on ag 111
Physical Review Letters, 2017Co-Authors: Reinhard J Maurer, Bin Jiang, John C TullyAbstract:Electronic friction and the ensuing nonadiabatic energy loss play an important role in chemical reaction dynamics at metal surfaces. Using molecular dynamics with electronic friction evaluated on the fly from density functional theory, we find strong mode dependence and a dominance of nonadiabatic energy loss along the bond stretch coordinate for scattering and Dissociative Chemisorption of H2 on the Ag(111) surface. Exemplary trajectories with varying initial conditions indicate that this mode specificity translates into modulated energy loss during a Dissociative Chemisorption event. Despite minor nonadiabatic energy loss of about 5%, the directionality of friction forces induces dynamical steering that affects individual reaction outcomes, specifically for low-incidence energies and vibrationally excited molecules. Mode-specific friction induces enhanced loss of rovibrational rather than translational energy and will be most visible in its effect on final energy distributions in molecular scattering experiments.
Geertjan Kroes - One of the best experts on this subject based on the ideXlab platform.
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curious mechanism of the Dissociative Chemisorption of ammonia on ru 0001
Journal of Physical Chemistry C, 2019Co-Authors: Nick Gerrits, Geertjan KroesAbstract:Dissociative Chemisorption of polyatomic molecules on metals, which is relevant to heterogeneous catalysis, usually proceeds through a rotationally adiabatic or rotational sudden mechanism. The reaction is usually either direct or proceeds through a trapped molecular chemisorbed state. Here, ab initio molecular dynamics is used to model the Dissociative Chemisorption of ammonia on Ru(0001). The reaction mechanism is neither rotationally adiabatic nor rotational sudden, with clearly distinct and nonstatistical initial and time-of-reaction orientation distributions. A reasonably good agreement is obtained between the computed and previously measured sticking probabilities. Under the conditions investigated, the reaction of NH3 goes through a molecular Chemisorption-like state, but the reaction is direct.
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dynamical study of the Dissociative Chemisorption of chd3 on pd 111
Journal of Physical Chemistry C, 2019Co-Authors: Nick Gerrits, Helen Chadwick, Geertjan KroesAbstract:The specific reaction parameter (SRP) approach to density functional theory has been shown to model reactions of polyatomic molecules with metal surfaces important for heterogeneous catalysis in th...
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Dissociative Chemisorption of methane on metal surfaces tests of dynamical assumptions using quantum models and ab initio molecular dynamics
Journal of Chemical Physics, 2014Co-Authors: Bret Jackson, Francesco Nattino, Geertjan KroesAbstract:The Dissociative Chemisorption of methane on metal surfaces is of great practical and fundamental importance. Not only is it the rate-limiting step in the steam reforming of natural gas, the reaction exhibits interesting mode-selective behavior and a strong dependence on the temperature of the metal. We present a quantum model for this reaction on Ni(100) and Ni(111) surfaces based on the reaction path Hamiltonian. The Dissociative sticking probabilities computed using this model agree well with available experimental data with regard to variation with incident energy, substrate temperature, and the vibrational state of the incident molecule. We significantly expand the vibrational basis set relative to earlier studies, which allows reaction probabilities to be calculated for doubly excited initial vibrational states, though it does not lead to appreciable changes in the reaction probabilities for singly excited initial states. Sudden models used to treat the center of mass motion parallel to the surface ...
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quantum dynamics of Dissociative Chemisorption of ch4 on ni 111 influence of the bending vibration
Journal of Chemical Physics, 2010Co-Authors: G P Krishnamohan, Fabien Gatti, Geertjan Kroes, R A Olsen, Sylvain WoittequandAbstract:Two-dimensional, three-dimensional, and four-dimensional quantum dynamic calculations are performed on the Dissociative Chemisorption of CH4 on Ni(111) using the multiconfiguration time-dependent Hartree (MCTDH) method. The potential energy surface used for these calculations is 15-dimensional (15D) and was obtained with density functional theory for points which are concentrated in the region that is dynamically relevant to reaction. Many reduced dimensionality calculations were already performed on this system, but the molecule was generally treated as pseudodiatomic. The main improvement of our model is that we try to describe CH4 as a polyatomic molecule by including a degree of freedom describing a bending vibration in our three-dimensional and four-dimensional models. Using a polyspherical coordinate system, a general expression for the 15D kinetic energy operator is derived, which discards all the singularities in the operator and includes rotational and Coriolis coupling. We use seven rigid constr...
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reactive and nonreactive scattering of n2 from ru 0001 a six dimensional adiabatic study
Journal of Chemical Physics, 2006Co-Authors: Cristina Diaz, Geertjan Kroes, G P Krishnamohan, R A Olsen, Jonathan Vincent, Karoliina Honkala, Jens K NorskovAbstract:We have studied the Dissociative Chemisorption and scattering of N2 on and from Ru(0001), using a six-dimensional quasiclassical trajectory method. The potential energy surface, which depends on all the molecular degrees of freedom, has been built applying a modified Shepard interpolation method to a data set of results from density functional theory, employing the RPBE generalized gradient approximation. The frozen surface and Born-Oppenheimer [Ann. Phys. (Leipzig) 84, 457 (1927)] approximations were used, neglecting phonons and electron-hole pair excitations. Dissociative Chemisorption probabilities are found to be very small even for translational energies much higher than the minimum reaction barrier, in good agreement with experiment. A comparison to previous low dimensional calculations shows the importance of taking into account the multidimensional effects of N2 rotation and translation parallel to the surface. The new calculations strongly suggest a much smaller role of nonadiabatic effects than ...
Hua Guo - One of the best experts on this subject based on the ideXlab platform.
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Dissociative Chemisorption of o2 on al 111 dynamics on a correlated wave function based potential energy surface
Journal of Physical Chemistry Letters, 2018Co-Authors: Rongrong Yin, Hua Guo, Yaolong Zhang, Florian Libisch, Emily A Carter, Bin JiangAbstract:Dissociative Chemisorption of O2 on the Al(111) surface represents an extensively studied prototype for understanding the interaction between O2 and metal surfaces. It is well known that the experimentally observed activation barrier for O2 dissociation is not captured by conventional density functional theory. The interpretation of this barrier as a result of spin transitions along the reaction path has been challenged by recent embedded correlated wave function (ECW) calculations that naturally yield an adiabatic barrier. However, the ECW calculations have been limited to a static analysis of the reaction pathways and have not yet been tested by dynamics simulations. We present a global six-dimensional potential energy surface (PES) for this system parametrized with ECW data points. This new PES provides a reasonable description of the site-specific and orientation-dependent activation barriers. Quasi-classical trajectory calculations on this PES semiquantitatively reproduce both the observed translatio...
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Dissociative Chemisorption of O2 on Al(111): Dynamics on a Correlated Wave-Function-Based Potential Energy Surface
2018Co-Authors: Rongrong Yin, Hua Guo, Yaolong Zhang, Florian Libisch, Emily A Carter, Bin JiangAbstract:Dissociative Chemisorption of O2 on the Al(111) surface represents an extensively studied prototype for understanding the interaction between O2 and metal surfaces. It is well known that the experimentally observed activation barrier for O2 dissociation is not captured by conventional density functional theory. The interpretation of this barrier as a result of spin transitions along the reaction path has been challenged by recent embedded correlated wave function (ECW) calculations that naturally yield an adiabatic barrier. However, the ECW calculations have been limited to a static analysis of the reaction pathways and have not yet been tested by dynamics simulations. We present a global six-dimensional potential energy surface (PES) for this system parametrized with ECW data points. This new PES provides a reasonable description of the site-specific and orientation-dependent activation barriers. Quasi-classical trajectory calculations on this PES semiquantitatively reproduce both the observed translational energy dependence of the sticking probability and steric effects with aligned O2 molecules
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Bond-Selective and Mode-Specific Dissociation of CH3D and CH2D2 on Pt(111)
2016Co-Authors: Morten P. Hundt, Bin Jiang, Hua Guo, Hirokazu Ueta, Maarten E. Van Reijzen, Rainer D. BeckAbstract:ABSTRACT: Infrared laser excitation of partially deuterated methanes (CH3D and CH2D2) in a molecular beam is used to control their Dissociative Chemisorption on a Pt(111) single crystal and to determine the quantum state-resolved dissociation probabilities. The exclusive detection of C−H cleavage products adsorbed on the Pt(111) surface by infrared absorption reflection spectroscopy indicates strong bond selectivity for both methane isotopologues upon C−H stretch excitation. Furthermore, the Dissociative Chemisorption of both methane isotopologues is observed to be mode-specific. Excitation of symmetric C−H stretch modes produces a stronger reactivity increase than excitation of the antisymmetric C−H stretch modes, whereas bend overtone excitation has a weaker effect on reactivity. The observed mode specificity and bond selectivity are rationalized by the sudden vector projection model in terms of the overlap of the reactant’s normal mode vectors with the reaction coordinate at the transition state. Ever since the invention of the laser in 1960, chemists have strived toward laser control of chemical reactions. Starting in 1990, the groups of Crim and Zare1,2 reported a number o
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towards an accurate specific reaction parameter density functional for water dissociation on ni 111 rpbe versus pw91
Physical Chemistry Chemical Physics, 2016Co-Authors: Bin Jiang, Hua GuoAbstract:In search for an accurate description of the Dissociative Chemisorption of water on the Ni(111) surface, we report a new nine-dimensional potential energy surface (PES) based on a large number of density functional theory points using the RPBE functional. Seven-dimensional quantum dynamical calculations have been carried out on the RPBE PES, followed by site averaging and lattice effect corrections, yielding sticking probabilities that are compared with both the previous theoretical results based on a PW91 PES and experiment. It is shown that the RPBE functional increases the reaction barrier, but has otherwise a minor impact on the PES topography. Better agreement with experimental results is obtained with the new PES, but the agreement is still not quantitative. Possible sources of the remaining discrepancies are discussed.
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communication energy transfer and reaction dynamics for dcl scattering on au 111 an ab initio molecular dynamics study
Journal of Chemical Physics, 2016Co-Authors: Brian Kolb, Hua GuoAbstract:Scattering and Dissociative Chemisorption of DCl on Au(111) are investigated using ab initio molecular dynamics with a slab model, in which the top two layers of Au are mobile. Substantial kinetic energy loss in the scattered DCl is found, but the amount of energy transfer is notably smaller than that observed in the experiment. On the other hand, the Dissociative Chemisorption probability reproduces the experimental trend with respect to the initial kinetic energy, but is about one order of magnitude larger than the reported initial sticking probability. While the theory-experiment agreement is significantly improved from the previous rigid surface model, the remaining discrepancies are still substantial, calling for further scrutiny in both theory and experiment.
Bret Jackson - One of the best experts on this subject based on the ideXlab platform.
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the Dissociative Chemisorption of co2 on ni 100 a quantum dynamics study
Journal of Chemical Physics, 2017Co-Authors: Azar Farjamnia, Bret JacksonAbstract:A quantum approach based on an expansion in vibrationally adiabatic eigenstates is used to explore the Dissociative Chemisorption of CO2 on Ni(100). The largest barrier to reaction corresponds to the formation of a bent anionic molecular precursor, bound to the surface by about 0.24 eV. The barrier to dissociation from this state is small. Our computed Dissociative sticking probabilities on Ni(100) for molecules in the ground state are in very good agreement with available experimental data, reasonably reproducing the variation in reactivity with collision energy. Vibrational excitation of the incident CO2 can enhance reactivity, particularly for incident energies at or below threshold, and there is clear mode specific behavior. Both the vibrational enhancement and the increase in Dissociative sticking with surface temperature are much weaker than that found in recent studies of methane and water Dissociative Chemisorption. The energetics for CO2 adsorption and dissociation on the stepped Ni(711) surface ...
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mode selective chemistry on metal surfaces the Dissociative Chemisorption of ch4 on pt 111
Journal of Chemical Physics, 2016Co-Authors: Bret JacksonAbstract:A quantum approach based on an expansion in vibrationally adiabatic eigenstates is used to explore CH4 dissociation on Pt(111). Computed sticking probabilities for molecules in the ground, 1v3 and 2v3, states are in very good agreement with the available experimental data, reproducing the variation in reactivity with collision energy and vibrational state. As was found in similar studies on Ni(100) and Ni(111), exciting the 1v1 symmetric stretch of CH4 is more effective at promoting the Dissociative Chemisorption of CH4 than exciting the 1v3 antisymmetric stretch. This behavior is explained in terms of symmetry, mode-softening, and nonadiabatic transitions between vibrationally adiabatic states. We find that the efficacies of the bending modes for promoting reaction are reasonably large, and similar to the 1v3 state. The vibrational efficacies for promoting reaction on Ni(111) are larger than for reaction on Pt(111), due to the larger nonadiabatic couplings. Our computed sticking probabilities are in good...
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the Dissociative Chemisorption of water on ni 111 mode and bond selective chemistry on metal surfaces
Journal of Chemical Physics, 2015Co-Authors: Azar Farjamnia, Bret JacksonAbstract:A fully quantum approach based on an expansion in vibrationally adiabatic eigenstates is used to explore the Dissociative Chemisorption of H2O, HOD, and D2O on Ni(111). For this late barrier system, excitation of both the bending and stretching modes significantly enhances Dissociative sticking. The vibrational efficacies vary somewhat from mode-to-mode but are all relatively close to one, in contrast to methane dissociation, where the behavior is less statistical. Similar to methane dissociation, the motion of lattice atoms near the dissociating molecule can significantly modify the height of the barrier to dissociation, leading to a strong variation in Dissociative sticking with substrate temperature. Given a rescaling of the barrier height, our results are in reasonable agreement with measurements of the Dissociative sticking of D2O on Ni(111), for both laser-excited molecules with one or two quanta of excitation in the antisymmetric stretch and in the absence of laser excitation. Even without laser excitation, the beam contains vibrationally excited molecules populated at the experimental source temperature, and these make significant contributions to the sticking probability. At high collision energies, above the adiabatic barrier heights, our results correlate with these barrier heights and mode softening effects. At lower energies, Dissociative sticking occurs primarily via vibrationally nonadiabatic pathways. We find a preference for O–H over O–D bond cleavage for ground state HOD molecules at all but the highest collision energies, and excitation of the O–H stretch gives close to 100% O–H selectivity at lower energies. Excitation of the O–D stretch gives a lower O–D cleavage selectivity, as the interaction with the surface leads to energy transfer from the O–D stretch into the O–H bond, when mode softening makes these vibrations nearly degenerate.
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Dissociative Chemisorption of methane on metal surfaces tests of dynamical assumptions using quantum models and ab initio molecular dynamics
Journal of Chemical Physics, 2014Co-Authors: Bret Jackson, Francesco Nattino, Geertjan KroesAbstract:The Dissociative Chemisorption of methane on metal surfaces is of great practical and fundamental importance. Not only is it the rate-limiting step in the steam reforming of natural gas, the reaction exhibits interesting mode-selective behavior and a strong dependence on the temperature of the metal. We present a quantum model for this reaction on Ni(100) and Ni(111) surfaces based on the reaction path Hamiltonian. The Dissociative sticking probabilities computed using this model agree well with available experimental data with regard to variation with incident energy, substrate temperature, and the vibrational state of the incident molecule. We significantly expand the vibrational basis set relative to earlier studies, which allows reaction probabilities to be calculated for doubly excited initial vibrational states, though it does not lead to appreciable changes in the reaction probabilities for singly excited initial states. Sudden models used to treat the center of mass motion parallel to the surface ...
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the Dissociative Chemisorption of methane on ni 111 the effects of molecular vibration and lattice motion
Journal of Chemical Physics, 2013Co-Authors: Bret Jackson, Sven NaveAbstract:We examine the Dissociative Chemisorption of methane on a Ni(111) surface, using a fully quantum approach based on the Reaction Path Hamiltonian that includes all 15 molecular degrees of freedom and the effects of lattice motion. The potential energy surface and all parameters in our model are computed from first principles. Vibrational excitation of the molecule is shown to significantly enhance the reaction probability, and the efficacy for this is explained in terms of the vibrationally non-adiabatic couplings, vibrational mode softening, and mode symmetry. Agreement with experimental data for molecules initially in the ground and 1ν3 state is good, and including lattice anharmonicity further improves our results. The variation of the dissociation probability with substrate temperature is well reproduced by the model, and is shown to result primarily from changes in the dissociation barrier height with lattice motion. The enhancement of Dissociative sticking with substrate temperature is particularly s...
Maite Alducin - One of the best experts on this subject based on the ideXlab platform.
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electron hole pair effects in methane Dissociative Chemisorption on ni 111
Journal of Chemical Physics, 2016Co-Authors: Maite Alducin, Inaki J JuaristiAbstract:The Dissociative Chemisorption of methane on metal surfaces has attracted much attention in recent years as a prototype of gas-surface reactions in understanding the mode specific and bond selective chemistry. In this work, we systematically investigate the influence of electron-hole pair excitations on the Dissociative Chemisorption of CH4/CH3D/CHD3 on Ni(111). The energy dissipation induced by surface electron-hole pair excitations is modeled as a friction force introduced in the generalized Langevin equation, in which the independent atomic friction coefficients are determined within the local-density friction approximation. Quasi-classical trajectory calculations for CH4/CH3D/CHD3 have been carried out on a recently developed twelve-dimensional potential energy surface. Comparing the dissociation probabilities obtained with and without friction, our results clearly indicate that the electron-hole pair effects are generally small, both on absolute reactivity of each vibrational state and on the mode specificity and bond selectivity. Given similar observations in both water and methane dissociation processes, we conclude that electron-hole pair excitations would not play an important role as long as the reaction is direct and the interaction time between the molecule and metal electrons is relatively short.
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electron hole pair effects in polyatomic Dissociative Chemisorption water on ni 111
Journal of Physical Chemistry Letters, 2016Co-Authors: Bin Jiang, Maite AlducinAbstract:The influence of electron–hole pairs in Dissociative Chemisorption of a polyatomic molecule (water) on metal surfaces is assessed for the first time using a friction approach. The atomic local density dependent friction coefficients computed based on a free electron gas embedding model are employed in classical molecular dynamics simulations of the water dissociation dynamics on rigid Ni(111) using a recently developed nine dimensional interaction potential energy surface for the system. The results indicate that nonadiabatic effects are relatively small and they do not qualitatively alter the mode specificity in the dissociation.