Orientation as a probe of photodissociation dynamics

Molecular chlorine (Cl2) was photodissociated in the wavelength range 270–400 nm with linearly polarized light, and the orientation of the excited-state chlorine atom Cl*(2P1/2) was measured by 2+1 resonance enhanced multiphoton ionization (REMPI) using circularly polarized light. The degree of orientation of the Cl* photofragment is found to oscillate as a function of photolysis wavelength. The oscillation is a result of quantum mechanical coherence arising from electronic states of different symmetry that correlate to the same separated-atom asymptote. A simple curve-crossing model using abinitio potential energy curves reproduces the general shape of the oscillation but fails to give a quantitative fit.

[1]  T. Kitsopoulos,et al.  Spin-orbit branching ratios for the Cl atom photofragments following the excitation of Cl2 from 310 to 470 nm , 1999 .

[2]  R. Zare,et al.  Measurements of Cl-atom photofragment angular momentum distributions in the photodissociation of Cl2 and ICl , 1999 .

[3]  R. Zare,et al.  PHOTOFRAGMENT ANGULAR MOMENTUM DISTRIBUTIONS IN THE MOLECULAR FRAME : DETERMINATION AND INTERPRETATION , 1999 .

[4]  C. Pei,et al.  Helicity of orientation parameters of photofragments in fluorescence-imaging experiments , 1998 .

[5]  J. L. Kinsey,et al.  Angular Distributions of Products in the Photodissociation of Diatomic Molecules , 1998 .

[6]  Zare,et al.  Photofragment helicity caused by matter-wave interference from multiple dissociative states , 1998, Science.

[7]  David H. Parker,et al.  Production of maximally aligned O(1D) atoms from two-step photodissociation of molecular oxygen , 1998 .

[8]  R. Zare,et al.  Photolysis of ICl causes mass-dependent interference in the Cl(2P3/2) photofragment angular momentum distributions , 1998 .

[9]  R. Zare,et al.  Core extraction for measuring state‐to‐state differential cross sections of bimolecular reactions , 1995 .

[10]  O. Vasyutinskii,et al.  Vector properties in photodissociation: Quantum treatment of the correlation between the spatial anisotropy and the angular momentum polarization of the fragments , 1994 .

[11]  R. Zare,et al.  Orientation and Alignment of Reaction Products , 1994 .

[12]  M. Kawasaki,et al.  Fine‐structure branching ratios and Doppler profiles of Cl(2Pj) photofragments from photodissociation of the chlorine molecule near and in the ultraviolet region , 1992 .

[13]  Richard N. Zare,et al.  Angular Momentum: Understanding Spatial Aspects in Chemistry and Physics , 1988 .

[14]  P. Houston.  Vector Correlations in Photodissociation Dynamics , 1987 .

[15]  R. Zare,et al.  Determination of population and alignment of the ground state using two‐photon nonresonant excitation , 1986 .

[16]  R. Dixon.  The determination of the vector correlation between photofragment rotational and translational motions from the analysis of Doppler‐broadened spectral line profiles , 1986 .

[17]  J. A. Coxon.  Revised molecular constants, RKR potential, and long-range analysis for the B3Π(0u+) state of Cl2, and rotationally dependent Franck-Condon factors for Cl2 (BX1Σg+) , 1980 .

[18]  R. Düren,et al.  Observation of polarization of atomic fluorescence excited by laser-induced dissociation of Na2 , 1980 .

[19]  B. R. Johnson.  New numerical methods applied to solving the one‐dimensional eigenvalue problem , 1977 .

[20]  R. Zare,et al.  Polarization of Atomic Fluorescence Excited by Molecular Dissociation , 1968 .