Comparison of the strong-field ionization of N{sub 2} and F{sub 2}: A time-dependent density-functional-theory study

Journal Article · Sat Jan 15 00:00:00 EST 2011 · Physical Review. A

DOI:https://doi.org/10.1103/PHYSREVA.83.013409· OSTI ID:21529099

Xi, Chu; McIntyre, Melissa ^[1]

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1. Department of Chemistry and Biochemistry, University of Montana, Missoula, Montana 59812 (United States)

We compare strong-field ionization probabilities of N{sub 2} and F{sub 2} molecules using time-dependent density functional theory calculations. Accurate nuclear potentials and ground vibrational wave functions are incorporated into our study. For both molecules, the effect of molecular vibration is small, while that of the molecular orientation is significant. When compared to the ionization probability of a molecule at the equilibrium geometry, we estimate the effect of the ground state vibration to be within 3% for N{sub 2} and within 6% for F{sub 2} in the intensity range from 1 to 5x10{sup 14} W/cm{sup 2}. The molecular-orientation-dependent ionization probabilities for both molecules at various intensities are presented. They are strongly dependent on the laser intensity, and the anisotropy diminishes when the laser intensity is high. For laser intensities of 1.6 and 2.2x10{sup 14} W/cm{sup 2} we find ionization probability ratios of 5.9 and 4.3, respectively, for the parallel versus perpendicular orientation of N{sub 2}. This is reasonably consistent with experimental measurements. For randomly oriented molecules, the ratio of the probabilities for N{sub 2} and F{sub 2} increases from about 1 at 10{sup 14} W/cm{sup 2} to 2 at 4x10{sup 14} W/cm{sup 2}, which agrees well with experimental results.

• OSTI ID: 21529099
• Journal Information: Physical Review. A, Vol. 83, Issue 1; Other Information: DOI: 10.1103/PhysRevA.83.013409; (c) 2011 American Institute of Physics; ISSN 1050-2947
• Country of Publication: United States
• Language: English

Related Subjects

74 ATOMIC AND MOLECULAR PHYSICS
ANISOTROPY
COMPARATIVE EVALUATIONS
DENSITY FUNCTIONAL METHOD
EQUILIBRIUM
FLUORINE
IONIZATION
LASER RADIATION
MOLECULES
NITROGEN
NUCLEAR POTENTIAL
ORIENTATION
PROBABILITY
TIME DEPENDENCE
WAVE FUNCTIONS
CALCULATION METHODS
ELECTROMAGNETIC RADIATION
ELEMENTS
EVALUATION
FUNCTIONS
HALOGENS
NONMETALS
POTENTIALS
RADIATIONS
VARIATIONAL METHODS