Rotational alignment of the CD sub 3 fragment from the 266-nm photodissociation of CD sub 3 I

Journal Article · Thu Oct 17 04:00:00 EDT 1991 · Journal of Physical Chemistry; (United States)

DOI:https://doi.org/10.1021/j100174a005· OSTI ID:7163217

Janssen, M H.M.; Parker, D H ^[1]; Sitz, G O ^[2]; Stolte, S ^[3]; Chandler, D W ^[4]

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1. Catholic Univ. of Nijmegen (Netherlands)
2. Univ. of Texas, Austin (United States)
3. Free Univ. of Amsterdam (Netherlands)
4. Sandia National Lab., Livermore, CA (United States)

The alignment of CD{sub 3} fragments created by photodissociation of CD{sub 3}I with linearly polarized 266-nm light is characterized by using the ion imaging technique. A linearly polarized probe laser is used for (2 + 1) resonance-enhanced multiphoton ionization (REMPI) of the methyl fragment. The three-dimensional velocity distribution of the state-selected CD{sub 3} ion is subsequently crushed onto a two-dimensional detector. Each position in the two-dimensional image corresponds to a different methyl fragment velocity, v. By measuring the dependence of the REMPI signal on the angle between the probe laser polarization and the photolysis laser polarization for specific parts of the image, the population n(N,K) and the alignment moments A{sub 0}{sup (2)} and A{sub 0}{sup (4)} of the angular momentum distribution of recoiling CD{sub 3} fragments are obtained with respect to v. These velocity-selective alignment moments describe the {cflx v}-{cflx N} correlation. The alignment moments extracted for single rotational levels (N,K) indicate that the rotational excitation produced in the photodissociation is about an axis perpendicular to the I-(CD{sub 3}) axis and that the initial rotation excitation produced in the photodissociation is about an axis perpendicular to the I-(CD{sub 3}) axis and that the initial rotation about the C{sub 3} axis of the parent is conserved in the methyl fragment. The alignment moments of the fragments recoiling along the direction of the photolysis transition dipole approach the maximum values expected for a purely axial recoil process, i.e., for a methyl fragment in the N,K rotational state, {vert bar}NKM{sub N}> = {vert bar}NKK>.

• OSTI ID: 7163217
• Journal Information: Journal of Physical Chemistry; (United States), Journal Name: Journal of Physical Chemistry; (United States) Vol. 95:21; ISSN 0022-3654; ISSN JPCHA
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400202 -- Isotope Effects
Isotope Exchange
& Isotope Separation
400500* -- Photochemistry
CHEMICAL REACTIONS
DATA
DECOMPOSITION
DEUTERIUM COMPOUNDS
ELECTROMAGNETIC RADIATION
ENERGY LEVELS
EXCITED STATES
HALOGENATED ALIPHATIC HYDROCARBONS
HYDROGEN COMPOUNDS
INFORMATION
IODINATED ALIPHATIC HYDROCARBONS
IONIZATION
ISOTOPE EFFECTS
MATHEMATICAL MODELS
METHYL IODIDE
NUMERICAL DATA
ORGANIC COMPOUNDS
ORGANIC HALOGEN COMPOUNDS
ORGANIC IODINE COMPOUNDS
PHOTOCHEMICAL REACTIONS
PHOTOIONIZATION
PHOTOLYSIS
POLARIZATION
RADIATIONS
ROTATIONAL STATES
THEORETICAL DATA
ULTRAVIOLET RADIATION