Vector signatures of adiabatic and diabatic dynamics in the photodissociation of ICN

Costen, M L; North, S W; Hall, G E

doi:10.1063/1.480041

Title: Vector signatures of adiabatic and diabatic dynamics in the photodissociation of ICN

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Abstract

Nascent Doppler profiles of CN (X&hthinsp;{sup 2}{summation}{sup +}) fragments from the {tilde A} band photodissociation of room temperature ICN have been measured using high-resolution transient frequency modulated absorption spectroscopy. Results for dissociation at 222 nm, 248 nm, 266 nm, and 308 nm are presented. From the Doppler profiles of multiple CN states, we determine branching ratios of the coincident atomic iodine states, and bipolar moments characterizing the CN velocity and angular momentum anisotropy. The measurements provide sensitive tests of the strengths of optical coupling to the excited states contributing to the {tilde A} band continuum, and the adiabatic and diabatic dynamics leading to the observed product states. Precise velocity measurements resolve differences in the average energy of the ICN molecules leading to selected fragment channels. We find a bond energy for ICN of 26&hthinsp;980{plus_minus}100&hthinsp;cm{sup {minus}1}, somewhat higher than previous literature values. {copyright} {ital 1999 American Institute of Physics.}

Authors:

Costen, M L; North, S W; Hall, G E ^[1]

Chemistry Department, Brookhaven National Laboratory, Upton, New York 11973-5000 (United States)

Publication Date:: Fri Oct 01 00:00:00 EDT 1999

OSTI Identifier:: 689942

Resource Type:: Journal Article

Journal Name:: Journal of Chemical Physics

Additional Journal Information:: Journal Volume: 111; Journal Issue: 15; Other Information: PBD: Oct 1999

Country of Publication:: United States

Language:: English

Subject:: 40 CHEMISTRY; 66 PHYSICS; PHOTOLYSIS; IODINE COMPOUNDS; CYANIDES; DISSOCIATION; ROTATIONAL STATES; ALIGNMENT; ANGULAR MOMENTUM; VELOCITY; IODINE; DOPPLER EFFECT; ULTRAVIOLET SPECTRA

Citation Formats


                    Costen, M L, North, S W, and Hall, G E. Vector signatures of adiabatic and diabatic dynamics in the photodissociation of ICN.  United States: N. p., 1999. 
        Web.  doi:10.1063/1.480041.

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                    Costen, M L, North, S W, & Hall, G E. Vector signatures of adiabatic and diabatic dynamics in the photodissociation of ICN.  United States.  https://doi.org/10.1063/1.480041

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                    Costen, M L, North, S W, and Hall, G E. 1999.  
        "Vector signatures of adiabatic and diabatic dynamics in the photodissociation of ICN".  United States.  https://doi.org/10.1063/1.480041.

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@article{osti_689942,

  title        = {Vector signatures of adiabatic and diabatic dynamics in the photodissociation of ICN},

  author       = {Costen, M L and North, S W and Hall, G E},

  abstractNote = {Nascent Doppler profiles of CN (X&hthinsp;{sup 2}{summation}{sup +}) fragments from the {tilde A} band photodissociation of room temperature ICN have been measured using high-resolution transient frequency modulated absorption spectroscopy. Results for dissociation at 222 nm, 248 nm, 266 nm, and 308 nm are presented. From the Doppler profiles of multiple CN states, we determine branching ratios of the coincident atomic iodine states, and bipolar moments characterizing the CN velocity and angular momentum anisotropy. The measurements provide sensitive tests of the strengths of optical coupling to the excited states contributing to the {tilde A} band continuum, and the adiabatic and diabatic dynamics leading to the observed product states. Precise velocity measurements resolve differences in the average energy of the ICN molecules leading to selected fragment channels. We find a bond energy for ICN of 26&hthinsp;980{plus_minus}100&hthinsp;cm{sup {minus}1}, somewhat higher than previous literature values. {copyright} {ital 1999 American Institute of Physics.}},

  doi          = {10.1063/1.480041},

  url          = {https://www.osti.gov/biblio/689942},
  journal      = {Journal of Chemical Physics},
number       = 15,

  volume       = 111,

  place        = {United States},

  year         = {Fri Oct 01 00:00:00 EDT 1999},

  month        = {Fri Oct 01 00:00:00 EDT 1999}

}

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