Anharmonic Effect of the Unimolecular Isomerization/Decomposition of Benzyne

The anharmonic and harmonic rate constants were calculated for the unimolecular decomposition of o-benzyne, the isomerization of o-benzyne to m-benzyne, the isomerization of m-benzyne to p-benzyne and unimolecular decomposition of p-benzyne by using the Rice–Ramsperger–Kassel–Marcus (RRKM) theory respectively, in the canonical and microcanonical systems. The geometry and the vibrational frequencies were calculated by MP2 and B3LYP methods with 6-311G(d,p) basis set and the barrier energies were corrected using CBS-QB3 theory. The anharmonic effect on the reactions was also examined. Comparison of results for the decompositions of benzyne indicate that both in microcanonical and canonical cases, the anharmonic effect on the decomposition of the o-C6H4 and p-C6H4 are significant, while the anharmonic effect on the two isomerizations are not pronounced.

[1]  L. Yao,et al.  Anharmonic effect of the unimolecular dissociation of CF 3 CX 2 O (X=F, H) Radicals , 2012 .

[2]  Yaoli,et al.  Anharmonic effect of the decomposition reaction of the CF3CCl2O radical , 2012 .

[3]  Jingjun Zhong,et al.  Anharmonic effect of dissociation rate constant of the ethoxy radical , 2010 .

[4]  A. Mebel,et al.  Dissociation rate constant of the hydrogen fluoride dimer by the ab initio anharmonic RRKM theory. , 2009, The journal of physical chemistry. A.

[5]  L. Yao,et al.  On the calculation of rate constants of the small cyclic water cluster by anharmonic RRKM theory , 2009 .

[6]  Alexander M. Mebel,et al.  On the calculation of the dissociation rate constant of the water dimer by the ab initio anharmonic RRKM theory , 2009 .

[7]  L. Yao,et al.  THEORETICAL STUDIES OF ANHARMONIC EFFECT IN THE RICE RAMSPERGER KASSEL MARCUS THEORY , 2008 .

[8]  L. Yao,et al.  The anharmonic effect study of coupled Morse oscillators for the unimolecular reaction , 2008 .

[9]  M. Hayashi,et al.  Theory of time-resolved sum-frequency generation and its applications to vibrational dynamics of water. , 2007, The journal of physical chemistry. A.

[10]  A. Mebel,et al.  Anharmonic effect on unimolecular reactions with application to the photodissociation of ethylene. , 2007, The journal of physical chemistry. A.

[11]  Andrew C. Simmonett,et al.  Unimolecular thermal fragmentation of ortho-benzyne. , 2007, The Journal of chemical physics.

[12]  S. McDowell.  The change in the vibrational anharmonicity for FH⋯Rg, FArH⋯Rg, FArH⋯N2 and FArH⋯P2 (Rg=Ne, Ar, Kr) , 2006 .

[13]  G. Wittig.  Phenyl-lithium, der Schlüssel zu einer neuen Chemie metallorganischer Verbindungen , 1942, Naturwissenschaften.

[14]  P. Thaddeus,et al.  Microwave spectrum of o-benzyne produced in a discharge nozzle , 2003 .

[15]  Joachim Sauer,et al.  The infrared spectrum of the O⋯H⋯O fragment of H5O2+: Ab initio classical molecular dynamics and quantum 4D model calculations , 2001 .

[16]  Pavel Hobza,et al.  Blue-Shifting Hydrogen Bonds. , 2000, Chemical reviews.

[17]  G. Chaban,et al.  Anharmonic Vibrational Spectroscopy of Hydrogen-Bonded Systems Directly Computed from ab Initio Potential Surfaces: (H2O)n, n = 2, 3; Cl-(H2O)n, n = 1, 2; H+(H2O)n, n = 1, 2; H2O−CH3OH , 2000 .

[18]  K. Song,et al.  Fitting classical microcanonical unimolecular rate constants to a modified RRK expression: Anharmonic and variational effects , 1999 .

[19]  L. Moskaleva,et al.  Unimolecular isomerization/decomposition of ortho-benzyne: ab initio MO/statistical theory study , 1999 .

[20]  W. Hase.  Some Recent Advances and Remaining Questions Regarding Unimolecular Rate Theory , 1998 .

[21]  Weiqiao Deng,et al.  Ab initio and RRKM calculations of o-benzyne pyrolysis , 1998 .

[22]  N. Turro,et al.  Photochemical Rearrangement of Enediynes: Is a "Photo-Bergman" Cyclization a Possibility? , 1998 .

[23]  Christopher J. Cramer,et al.  A reinvestigation of singlet benzyne thermochemistry predicted by CASPT2, coupled-cluster and density functional calculations , 1997 .

[24]  L. Moskaleva,et al.  Ab Initio MO Study of the Unimolecular Decomposition of the Phenyl Radical , 1997 .

[25]  Gilles H. Peslherbe,et al.  Statistical anharmonic unimolecular rate constants for the dissociation of fluxional molecules: Application to aluminum clusters , 1996 .

[26]  H. O. Pritchard,et al.  Sensitivity of molecular dynamics unimolecular rate calculations to defects in the potential-energy surface , 1996 .

[27]  W. Hase,et al.  Unimolecular reaction dynamics : theory and experiments , 1996 .

[28]  J. Troe.  SIMPLIFIED MODELS FOR ANHARMONIC NUMBERS AND DENSITIES OF VIBRATIONAL STATES. I: APPLICATION TO NO2 AND H3+ , 1995 .

[29]  Anders Bernhardsson,et al.  An Extended Ab Initio and Theoretical Thermodynamics Studies of the Bergman Reaction and the Energy Splitting of the Singlet Ortho-, Meta-, and Para-Benzynes , 1995 .

[30]  T. Doyle,et al.  Enediyne antibiotics as antitumor agents , 1995 .

[31]  M. Frenklach,et al.  Calculations of rate coefficients for the chemically activated reactions of acetylene with vinylic and aromatic radicals , 1994 .

[32]  Elfi Kraka,et al.  CCSD(T) Investigation of the Bergman Cyclization of Enediyne. Relative Stability of o-, m-, and p-Didehydrobenzene , 1994 .

[33]  S. Bhattacharyya,et al.  Multiphoton dissociation dynamics of SF6 via a completely rotationally resolved model , 1994 .

[34]  K. Lehmann,et al.  Numerical Laplace transform density of states calculation for medium and large molecules , 1993 .

[35]  K. Nicolaou,et al.  Molecular Design, Chemical Synthesis, and Biological Action of Enediynes , 1992 .

[36]  Sean C. Smith,et al.  Theory of Unimolecular and Recombination Reactions , 1990 .

[37]  J. Troe.  Specific rate constants k(E, J) for unimolecular bond fissions , 1983 .

[38]  W. Hase,et al.  Sum and density of states for anharmonic polyatomic molecules. Effect of bend–stretch coupling , 1983 .

[39]  V. Letokhov,et al.  Multiple-Photon Infrared Laser Photophysics and Photochemistry. II , 1983 .

[40]  W. Miller.  Tunneling Corrections to Unimolecular Rate Constants, with Application to Formaldehyde , 1979 .

[41]  J. Troe.  Predictive possibilities of unimolecular rate theory , 1979 .

[42]  J. Troe.  Theory of thermal unimolecular reactions at low pressures. II. Strong collision rate constants. Applications , 1977 .

[43]  S. Lin,et al.  Theory of vibrational relaxation and infrared absorption in condensed media , 1976 .

[44]  W. Forst,et al.  Theory of Unimolecular Reactions , 1973 .

[45]  Robert G. Bergman,et al.  p-Benzyne. Generation as an intermediate in a thermal isomerization reaction and trapping evidence for the 1,4-benzenediyl structure , 1972 .

[46]  W. Forst.  Methods for calculating energy-level densities , 1971 .

[47]  M. Hoare,et al.  Inversion of the Partition Function: The First‐Order Steepest‐Descent Method , 1970 .

[48]  P. Haarhoff.  The density of vibrational energy levels of polyatomic molecules , 1964 .

[49]  E. W. Schlag,et al.  Computation of Statistical Complexions as Applied to Unimolecular Reactions , 1962 .

[50]  John D. Roberts,et al.  Rearrangement in the Reaction of Chlorobenzene-1-C^(14) with Potassium Amide , 1953 .

[51]  G. Wittig,et al.  Über die Bildung von Diphenyl aus Fluorbenzol und Phenyl‐lithium (IV. Mitteil. über Austauschreaktionen mit Phenyl‐lithium) , 1940 .