The ClO4 radical: Experiment versus theory

The chlorine tetroxide radical and its anion have been investigated with unrestricted Hartree–Fock, density functional and hybrid Hartree–Fock/density functional methods, perturbation theory, and coupled cluster methods. It is predicted that the minimum on the ClO4 radical potential energy surface corresponds to the 2B2 ground electronic state, a C2v-symmetry structure. The C3v structure identified experimentally lies a few kcal mol−1 higher energetically. A Cs symmetry structure lies very close energetically to the C2v minimum at some levels of theory. Adiabatic electron affinities, equilibrium geometries, harmonic vibrational frequencies, infrared intensities, isotopic shifts, and dipole moments are presented for all methods. Comparisons with recent experimental vibrational data for the radical are made. It is predicted that the C2v equilibrium geometry of the ground state is Re(Cl–O1)=1.502 A, Re(Cl–O2)=1.424 A, θe1=93.6° and θe2=114.2°. The adiabatic electron affinity of the ClO4 radical is predicted ...

[1]  G. Scuseria,et al.  Comparison of coupled-cluster methods which include the effects of connected triple excitations , 1990 .

[2]  K. Schwarz.  Instability of stable negative ions in the Xα method or other local density functional schemes , 1978 .

[3]  H. Schaefer,et al.  COMMUNICATIONS Concerning the applicability of density functional methods to atomic and molecular negative ions , 1996 .

[4]  H. Schaefer,et al.  Negative Ion Thermochemistry: The Sulfur Fluorides SFn/SFn- (n = 1−7) , 1996 .

[5]  John A. Pople,et al.  Approximate fourth-order perturbation theory of the electron correlation energy , 1978 .

[6]  M. Head‐Gordon,et al.  A fifth-order perturbation comparison of electron correlation theories , 1989 .

[7]  H. Eysel.  Raman intensities of liquids: absolute scattering activities and ClO bond EOPs of ClO−, ClO−2, ClO−3 and ClO−4 ions in aqueous solution , 1988 .

[8]  S. Jensen,et al.  ESR Spectra from Paramagnetic Centers in Irradiated KClO4. III. Centers Appearing between 10 and 200°K , 1970 .

[9]  Harry Partridge,et al.  The sensitivity of B3LYP atomization energies to the basis set and a comparison of basis set requirements for CCSD(T) and B3LYP , 1995 .

[10]  R. Caminiti,et al.  Ab initio SCF study on LiClO4 and Li2SO4 molecules: Geometries and vibrational frequencies , 1991 .

[11]  A. Colussi,et al.  Kinetics and thermochemistry of chlorine- and nitrogen-containing oxides and peroxides , 1993 .

[12]  Parr,et al.  Development of the Colle-Salvetti correlation-energy formula into a functional of the electron density. , 1988, Physical review. B, Condensed matter.

[13]  A. D. McLean,et al.  Contracted Gaussian basis sets for molecular calculations. I. Second row atoms, Z=11–18 , 1980 .

[14]  Gregory S. Tschumper,et al.  Structures, thermochemistry, and electron affinities of the PFn and PF−n series, n=1–6 , 1996 .

[15]  J. Morton.  Electron Spin Resonance Spectrum of ClO4 Trapped in Irradiated KClO4 , 1966 .

[16]  J. H. Rose,et al.  Failure of the local exchange approximation in the evaluation of the H/sup -/ ground state , 1977 .

[17]  A. Becke.  A New Mixing of Hartree-Fock and Local Density-Functional Theories , 1993 .

[18]  E. Davidson,et al.  The electron affinity of oxygen: A systematic configuration interaction approach , 1989 .

[19]  A. Becke,et al.  Density-functional exchange-energy approximation with correct asymptotic behavior. , 1988, Physical review. A, General physics.

[20]  Michael J. Frisch,et al.  MP2 energy evaluation by direct methods , 1988 .

[21]  T. Crawford,et al.  The balance between theoretical method and basis set quality: A systematic study of equilibrium geometries, dipole moments, harmonic vibrational frequencies, and infrared intensities , 1993 .

[22]  Curtis L. Janssen,et al.  An efficient reformulation of the closed‐shell coupled cluster single and double excitation (CCSD) equations , 1988 .

[23]  M. Jansen,et al.  Properties of dichlorine hexaoxide in the gas phase and in low-temperature matrixes , 1988 .

[24]  J. Perdew,et al.  Calculated electron affinities of the elements , 1982 .

[25]  Gustavo E. Scuseria,et al.  The open-shell restricted Hartree—Fock singles and doubles coupled-cluster method including triple excitations CCSD (T): application to C+3 , 1991 .

[26]  A. Becke.  Density-functional thermochemistry. III. The role of exact exchange , 1993 .

[27]  E. C. Curtis,et al.  The general valence force field of perchloryl fluoride , 1981 .

[28]  T. H. Dunning.  Gaussian Basis Functions for Use in Molecular Calculations. III. Contraction of (10s6p) Atomic Basis Sets for the First‐Row Atoms , 1970 .

[29]  K. A. Oakes,et al.  Matrix isolation study of S2O6F2 pyrolysis products: The infrared spectrum of SO3F radical , 1975 .

[30]  K. Schwarz.  First ionisation potentials of atoms obtained with local-density schemes , 1978 .

[31]  H. Siebert.  Kraftkonstante und Strukturchemie. V. Struktur der Sauerstoffsäuren , 1954 .

[32]  Rodney J. Bartlett,et al.  An open-shell spin-restricted coupled cluster method: application to ionization potentials in nitrogen , 1988 .

[33]  Henry F. Schaefer,et al.  A systematic theoretical study of harmonic vibrational frequencies: The ammonium ion NH4+ and other simple molecules , 1980 .

[34]  Julia E. Rice,et al.  The closed‐shell coupled cluster single and double excitation (CCSD) model for the description of electron correlation. A comparison with configuration interaction (CISD) results , 1987 .

[35]  John P. Perdew,et al.  A self-interaction corrected approach to many-electron systems: Beyond the local spin density approximation , 1980 .

[36]  J. Perdew.  Orbital functional for exchange and correlation: self-interaction correction to the local density approximation☆ , 1979 .

[37]  Michael J. Frisch,et al.  A direct MP2 gradient method , 1990 .

[38]  Michael J. Frisch,et al.  Semi-direct algorithms for the MP2 energy and gradient , 1990 .

[39]  H. Schaefer,et al.  The monochlorine fluorides (ClFn) and their anions (ClFn-) n = 1-7: structures and energetics , 1996 .

[40]  H. Schaefer,et al.  Systematic study of molecular anions within the self‐consistent‐field approximation: OH−, CN−, C2H−, NH−2, and CH−3 , 1985 .

[41]  S. H. Vosko,et al.  Accurate spin-dependent electron liquid correlation energies for local spin density calculations: a critical analysis , 1980 .

[42]  E. M. Evleth,et al.  Comparison of ab initio and AMSOL semiempirical free energies of solvation of third-row species , 1994 .

[43]  G. Scuseria,et al.  A systematic theoretical study of harmonic vibrational frequencies: The single and double excitation coupled cluster (CCSD) method , 1988 .

[44]  J. Heicklen,et al.  Perchloric acid: A possible sink for stratospheric chlorine , 1975 .

[45]  M. Molina,et al.  Stratospheric sink for chlorofluoromethanes: chlorine atomc-atalysed destruction of ozone , 1974, Nature.

[46]  R. Bartlett,et al.  A full coupled‐cluster singles and doubles model: The inclusion of disconnected triples , 1982 .

[47]  W. Kohn,et al.  Self-Consistent Equations Including Exchange and Correlation Effects , 1965 .

[48]  J. Barker.  Progress and Problems in Atmospheric Chemistry , 1995 .