The Experts below are selected from a list of 34227 Experts worldwide ranked by ideXlab platform
S.a. Mitchell - One of the best experts on this subject based on the ideXlab platform.
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Association Reactions of nickel atoms with carbon monoxide and alkenes at room temperature: binding energy of NiC2H4
Chemical Physics Letters, 1992Co-Authors: C. E. Brown, S.a. Mitchell, Peter A. HackettAbstract:Abstract We report a kinetic study of Association Reactions of nickel atoms with carbon monoxide, ethene, propene and 1-butene in carbon dioxide buffer gas in the pressure range 1–600 Torr at 296 K. RRKM theory is used together with results of previous ab initio electronic structure calculations to interpret Association rate coefficients in terms of binding energies of 1:1 complexes. The binding energy of NiC 2 H 4 at 0 K is estimated as 35.5±5 kcal mol −1 . The role of excited electronic states of the complexes in the Association Reactions is briefly discussed.
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Association Reactions of transition metal atoms with simple molecules near room temperature
Gas Phase Metal Reactions, 1992Co-Authors: S.a. MitchellAbstract:Abstract An experimental method for studies of Association Reactions of transition metal atoms with simple molecules near room temperature is described, and results for Cr, Fe, Ni and Cu atom Reactions with CO, C2H4 and O2 are discussed. Attention is given to methods for obtaining information on binding energies of 1:1 complexes from kinetic data. The use of unimolecular reaction theory to model Association rate coefficients at low pressure is discussed in detail, and several examples are given of estimates of binding energies from such modeling studies. Results for NiC2H4 are in good agreement with theoretical predictions. Progress in this area depends on the availability of information from experiment or theory on structural and electronic properties of Association complexes.
Robert C. Dunbar - One of the best experts on this subject based on the ideXlab platform.
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Radiative Association Reactions of Na+, Mg+, and Al+ with Abundant Interstellar Molecules. Variational Transition State Theory Calculations
The Journal of Physical Chemistry A, 2000Co-Authors: Simon Petrie, Robert C. DunbarAbstract:Ab initio calculations using G2 theory and other methods have been performed for the collision complexes of the metal ions Na+, Mg+, and Al+ with the molecules H2, CO, N2, NH3, H2O, HCN, HNC, C2H2, C2H4, c−C3H2, H2CCC, H2CCCC, and HCCCN. Binding energies, vibrational frequencies, and infrared intensities obtained from these calculations have been used to perform variational transition state theory (VTST) calculations for the corresponding radiative Association Reactions at temperatures pertinent to dense interstellar clouds and the outer regions of circumstellar envelopes. The calculated rate coefficients for radiative Association Reactions with H2 and with the other smaller molecules of this group are slow compared with the chemical evolutionary time scale of cold interstellar clouds. For the largest and most strongly bound complexes considered, the rate of depletion of M+ by this mechanism becomes competitive with recombination of M+ with free electrons. Predicted rates for Association in several system...
Craig C. Martens - One of the best experts on this subject based on the ideXlab platform.
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The role of microscopic solvation in the Association reaction I–Ar12+I
The Journal of Chemical Physics, 1992Co-Authors: Craig C. MartensAbstract:Molecular dynamics investigation of a prototypical model reaction I–Arn(n=12)+I reveals the role of microscopic solvation in Association Reactions: (a) enhancement of capture cross section of the incident I atom; (b) mediation of the migration of I to form I2; and (c) stabilization of I2 product by evaporative cooling.
Toshihiro Fujii - One of the best experts on this subject based on the ideXlab platform.
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alkali metal ion molecule Association Reactions and their applications to mass spectrometry
Mass Spectrometry Reviews, 2000Co-Authors: Toshihiro FujiiAbstract:This review will be concerned primarily with thermal alkali-metal ion Association Reactions of the general type: A+ + M + N ⇌ (A + M)+ + N. Where A denotes a positively charged alkali metal ion, M is neutral species and N works as a third body. As indicated, most Association Reactions are reversible, and the AM bond derives primarily from electrostatic forces whose energy (affinity) is typically 50 kcal/mol or less, often much less. The review includes reaction mechanism, instrumentation, and application to mass spectrometry, together with reaction rates and alkali ion affinities of the classified compounds. © 2000 John Wiley & Sons, Inc., Mass Spec Rev 19: 111–138, 2000
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Alkali-metal ion/molecule Association Reactions and their applications to mass spectrometry
Mass spectrometry reviews, 2000Co-Authors: Toshihiro FujiiAbstract:This review will be concerned primarily with thermal alkali-metal ion Association Reactions of the general type: A+ + M + N ⇌ (A + M)+ + N. Where A denotes a positively charged alkali metal ion, M is neutral species and N works as a third body. As indicated, most Association Reactions are reversible, and the AM bond derives primarily from electrostatic forces whose energy (affinity) is typically 50 kcal/mol or less, often much less. The review includes reaction mechanism, instrumentation, and application to mass spectrometry, together with reaction rates and alkali ion affinities of the classified compounds. © 2000 John Wiley & Sons, Inc., Mass Spec Rev 19: 111–138, 2000
Donald G Truhlar - One of the best experts on this subject based on the ideXlab platform.
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cluster and nanoparticle condensation and evaporation Reactions thermal rate constants and equilibrium constants of alm aln m aln with n 2 60 and m 1 8
Journal of Physical Chemistry C, 2008Co-Authors: Zhen Hua Li, Donald G TruhlarAbstract:The Association Reactions of Al atoms with Aln clusters and nanoparticles and the unimolecular dissociation Reactions of Aln clusters and nanoparticles have been studied using classical molecular dynamics trajectory simulations. Thermal reaction rate constants of the Association rate constant with m = 1 and the dissociation rate constant with m = 1−8 have been simulated, and subsequently, the Association rate constants for m > 1 can be determined indirectly. It was found that the monomer Association rate constants depend weakly on temperature. For the unimolecular dissociation Reactions, the rate constants depend strongly on temperature, and the temperature dependences can be fitted using the Arrhenius equation. The results indicate that the unimolecular dissociation reaction has a high activation barrier that tends to increase with particle size and furthermore that the preferred dissociation process is always monomer emission. With both the monomer Association and monomer emission rate constants, the st...
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representative benchmark suites for barrier heights of diverse reaction types and assessment of electronic structure methods for thermochemical kinetics
Journal of Chemical Theory and Computation, 2007Co-Authors: Jingjing Zheng, Yan Zhao, Donald G TruhlarAbstract:We propose three small sets of barrier heights for heavy-atom transfer, nucleophilic substitution, and unimolecular and Association Reactions as benchmarks for comparing and developing theoretical methods. We chose the data sets to be statistically representative subsets of the NHTBH38/04 database. Each data set consists of 6 barrier heights; we call these small benchmark suites HATBH6, NSBH6, and UABH6. Benchmark values are tabulated for 205 combinations of theory level and basis set. The theory levels studied include single-level wave function theory like Hartree−Fock, Moller−Plesset perturbation theory, quadratic configuration interaction, and coupled cluster theory; they also include multicoefficient correlation methods, local and hybrid density functional theory, and semiempirical molecular orbital methods. The three new representative data sets are combined with a previous representative data set for hydrogen-transfer Reactions to form a new compact but diverse and representative data set called DBH...
