Internal energy distributions from nitrogen dioxide fluorescence. 2. Collisional energy transfer from excited nitrogen dioxide

Journal Article · Thu Sep 30 04:00:00 EDT 1993 · Journal of Physical Chemistry; (United States)

DOI:https://doi.org/10.1021/j100141a005· OSTI ID:5424624

Patten, Jr, K O; Johnston, H S ^[1]

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1. Univ. of California, Berkeley, CA (United States) Lawrence Berkeley Lab., CA (United States)

We follow the collisional deactivation of laser-excited nitrogen dioxide through its dispersed fluorescence. The energy acceptor gases are NO[sub 2] at four excitation energies ranging from 18828 to 24989 cm[sup [minus]1] and five monatomic gases, four diatomic gases, and three polyatomic gases with 18828-cm[sup [minus]1] excitation energy. The nominal products are the shapes of the internal energy distributions, which are obtained and plotted for several representative cases. From these distributions, the first three moments of the internal energy distributions are derived as a function of molecular collisions and tabulated as (i) the average internal energy, (ii) energy spread, and (iii) skewness. These quantities are plotted against c(M)t, the product of buffer gas concentration c(M) and delay time after laser excitation t(0.5-2 [mu]s), which is a quantity proportional to number of collisions. The negative slope of average energy vs c(M)t is the macroscopic energy-transfer rate constant, k[sub [epsilon]](M). Average energies (E) for all NO[sub 2]-buffered data taken at four excitation wavelengths are well represented by the single equation, fourth order in energy: d(E)/d(c[sub NO(2)]t) = [minus]k[sub 4](E)[sup 4], where k[sub 4] = 8.06 [times] 10[sup [minus]25] (cm[sup 3])[sub energy] molecule[sup [minus]1] cm[sup 3] s[sup [minus]1]. 32 refs., 16 figs., 7 tabs.

• DOE Contract Number: AC03-76SF00098
• OSTI ID: 5424624
• Journal Information: Journal of Physical Chemistry; (United States), Journal Name: Journal of Physical Chemistry; (United States) Vol. 97:39; ISSN JPCHAX; ISSN 0022-3654
• Country of Publication: United States
• Language: English

Related Subjects

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CHEMISTRY
400201* -- Chemical & Physicochemical Properties
400500 -- Photochemistry
CHALCOGENIDES
COLLISIONS
ELECTROMAGNETIC RADIATION
EMISSION SPECTROSCOPY
ENERGY LEVELS
ENERGY TRANSFER
EXCITED STATES
FLUORESCENCE
FLUORESCENCE SPECTROSCOPY
LASER RADIATION
LENNARD-JONES POTENTIAL
LUMINESCENCE
MOLECULE COLLISIONS
NITROGEN COMPOUNDS
NITROGEN DIOXIDE
NITROGEN OXIDES
OXIDES
OXYGEN COMPOUNDS
POTENTIALS
RADIATIONS
SPECTROSCOPY
VIBRATIONAL STATES