Nonequilibrium characteristics in the rotational temperature of CO excited states in microwave discharge CO2 plasma

Shota Yamada; Yuki Morita; Atsushi Nezu; Hiroshi Akatsuka

doi:10.35848/1347-4065/abee04

CRDS study of auto-ionizing Rydberg states of argon in a microwave discharge This article is part of a Special Issue on Spectroscopy at the University of New Brunswick in honour of Colan Linton and Ron Lees.

Canadian Journal of Physics ◽

10.1139/p08-132 ◽

2009 ◽

Vol 87 (5) ◽

pp. 575-581 ◽

Cited By ~ 1

Author(s):

B. M. van der Ende ◽

C. Winslade ◽

R. L. Brooks ◽

R. H. deLaat ◽

N. P.C. Westwood

Keyword(s):

New Brunswick ◽

Excited States ◽

Microwave Discharge ◽

Rydberg States ◽

Spectral Lines ◽

Optical Transitions ◽

Single Source ◽

Special Issue ◽

Line Widths ◽

The University

Optical transitions from two microwave discharge excited states of argon have been observed using cavity ring-down spectroscopy. These transitions originate on the high-lying levels, 3d[1/2] 1° and 3d[3/2] 2° , and terminate on the nf ′[5/2] Rydberg (n = 8 to 22) levels, which, except for n = 8, lie between the 2P3/2 and 2P1/2 ionization thresholds. In total, 24 such spectral lines have been observed. The quantum defect for the f ′ series has been measured and is compared to previously measured values. We observe a nearly threefold jump in line width in going from n = 8 to n = 9, below and above the 2P3/2 threshold, respectively. The line widths are broad and increase monotonically with n (above 9), in contrast to the narrowing of line widths usually observed. We cannot attribute this to a single source but conclude that collisional, quasielastic l-mixing of the nf ′[5/2] Rydberg states plays a significant role.

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THE HYDROGEN–CHLORINE SYSTEM IN THE MM PRESSURE RANGE: I. ENERGY DISTRIBUTION AMONG VIBRATIONALLY EXCITED STATES

Canadian Journal of Chemistry ◽

10.1139/v64-323 ◽

1964 ◽

Vol 42 (10) ◽

pp. 2176-2192 ◽

Cited By ~ 14

Author(s):

F. D. Findlay ◽

J. C. Polanyi

Keyword(s):

Excited States ◽

Rotational Temperature ◽

Relative Rate ◽

Infrared Emission ◽

Vibrational States ◽

Vibrationally Excited ◽

Experimental Conditions ◽

Reduced Pressure ◽

A Chain ◽

First Time

When atomic plus molecular hydrogen coming from a Wood's discharge tube are mixed with molecular chlorine, infrared emission is observed (1). At low reagent pressures, ~10−2 mm Hg, this emission can be related to the relative rate of the reaction H + Cl2 → HCl†ν + Cl proceeding to form HCl in vibrationally excited states ν = 1–6, of the ground electronic state. In the present work this system has been investigated for the first time at ~100 × the reagent pressure (~1 mm Hg). The reaction was shown to proceed by a chain mechanism. The translational–rotational temperature was 1300 ± 100 °K under the experimental conditions normally used. The vibrational distribution was notable for the presence of vibrators in levels ν = 7 and 8, which are respectively 4 and 10 kcal higher in energy than the exothermicity of the H + Cl2 reaction. The population in these levels appeared to be related to that in the levels with [Formula: see text]; it was proposed that vibrational–vibrational exchange among these lower levels was responsible for populating the higher ones. A simple model yielded a collision efficiency for HCl†ν=1 + HCl†ν=6 → HCl†ν=7 + HCl†ν=0, of Z1,6t = 6 × 103 collisions per transfer. Addition of HCl to the reaction mixture brought about a redistribution among vibrationally excited states indicative of a fast vibrational transfer, HClν=0 + HCl†ν=2 → 2 HCl†ν=1.At reduced pressure of HCl† the stationary-state distribution among higher vibrational states approximated closely to that observed at 10−2 mm Hg total pressure (where collisional deactivation is insignificant), suggesting that collisional deactivation was not of major importance even at the pressure used in the present work. In order to account for the high translational–rotational temperature, in the absence of substantial vibrational deactivation, it was necessary to suppose that the greater part of the energy liberated by the reaction H + Cl2 went directly into translational and rotational motion of the products.

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Vibrational Deactivation of Excited States of Nitrogen created in a Microwave Discharge

Nature ◽

10.1038/214589a0 ◽

1967 ◽

Vol 214 (5088) ◽

pp. 589-589 ◽

Cited By ~ 7

Author(s):

R. E. W. JANSSON ◽

L. A. MIDDLETON ◽

J. LEWIS

Keyword(s):

Excited States ◽

Microwave Discharge

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High temperature studies of singlet excited oxygen, O 2 ( 1 Σ g + ) and O 2 ( 1 Δ g ), with a combined discharge flow/shock tube method

Proceedings of the Royal Society of London Series A - Mathematical and Physical Sciences ◽

10.1098/rspa.1979.0095 ◽

1979 ◽

Vol 367 (1730) ◽

pp. 395-410 ◽

Cited By ~ 24

Keyword(s):

Steady State ◽

Shock Tube ◽

Excited States ◽

High Temperatures ◽

Rate Constants ◽

Microwave Discharge ◽

Discharge Flow ◽

Direct Collision ◽

State Concentration ◽

Excited Oxygen

The excited states of oxygen, O 2 ( 1 Δ g ) and O 2 ( 1 Σ g + ), generated in a microwave discharge, were shock heated in order to study their reactions at temperatures in the range 650-1650 K. The increase in the dimol emission (634 nm) from O 2 ( 1 Δ g ) behind the shock front is consistent with the simple collisional model for the production of the emission; the rate of quenching of O 2 ( 1 Δ g ) by O 2 is too slow to measure at high temperatures with the technique. The emission from O 2 ( 1 Σ g + ) increases because of the shock compression and then is further enhanced by a displacement in the steady state concentration which is maintained by the two reactions pooling: 2O 2 ( 1 Δ g )->O 2 ( 1 Σ g + )+O 2 ( 3 Σ g - ) k p ; quenching: O 2 ( 1 Σ g + )+M->O 2 ( 3 Σ g - or 1 Δ g )+M; k q M . The relaxation to the enhanced level of emission permits k M q to be measured directly and then k p is calculated from the enhanced steady state emission level and k M q . There is no evidence for direct, collision induced! enhancement of the emission from O 2 ( 1 Σ g + ). Curved Arrhenius plots of the rate constants were found; some values are given in table 2. The results appear to indicate that in each case there are two mechanisms operating; one involving short range forces, and the other, long range forces or a collision complex. An evaluation is given of the discharge flow-shock tube technique as a method for determining rate constants at high temperatures.

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A Highly Excited Ammonia Cloud at least 300 pc from the Galactic Centre

Publications of the Astronomical Society of Australia ◽

10.1017/s1323358000022177 ◽

1987 ◽

Vol 7 (2) ◽

pp. 185-188 ◽

Cited By ~ 8

Author(s):

F. F. Gardner ◽

F. Boes

Keyword(s):

Excited States ◽

High Temperatures ◽

Ground State ◽

Rotational Temperature ◽

Half Width ◽

Galactic Centre ◽

Central Concentration

AbstractA cloud with a l.s.r. velocity of ∼ 160 km s-1 and a half-width of ∼ 25 km s-1 was mapped in the (1,1), (2,2) and (4,4) lines of para NH3 and the (3,3) and (6,6) lines of ortho NH3 using the 40″ arc beam of the 100-m Effelsberg telescope. The cloud was extended some 5′ in latitude and contained a central concentration ∼ 1′.5 in size at ℓ = 1°.59; b=0°.01. Line temperatures of the four higher transitions define a rotational temperature of ∼ 120 K, while the (1,1) and (2,2) alone yield the lower value of ∼ 40 K. The high temperatures, well above that of the dust, are too high to be caused by collisions with H2 molecules in the ground state, but might result from collisions with H2 in excited states. On a (ℓ, v) plot the cloud does not coincide with any generally accepted galactic centre feature but it is possibly located near the periphery of the ‘rotating nuclear disk’, where conditions would be favourable for the production of shocks, excited H2 and possibly high NH3 temperatures.

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Vuv Spectra Y to Mo

International Astronomical Union Colloquium ◽

10.1017/s0252921100107808 ◽

1988 ◽

Vol 102 ◽

pp. 239

Author(s):

M.S.Z. Chaghtai

Keyword(s):

Excited States ◽

Spectral Analyses ◽

Vuv Spectra

Using R.D. Cowan’s computations (1979) and parametric calculations of Meinders et al (1982), old analyses are thoroughly revised and extended at Aligarh, of Zr III by Khan et al (1981), of Nb IV by Shujauddin et Chaghtai (1985), of Mo V by Tauheed at al (1985). Cabeza et al (1986) confirmed the last one largely.Extensive studies have been reported of the 1–e spectra, Zr IV (Rahimullah et al 1980; Acquista and Reader 1980), Nb V (Shujauddin et al 1982; Kagan et al 1981) and Mo VI (Edlén et al 1985). Some interacting 4p54d2levels of these spectra have been reported from our laboratory, also.Detailed spectral analyses of transitions between excited states have furnished complete energy values for J ≠ 1 levels of these spectra during 1970s and 80s. Shujauddin et al (1982) have worked out Nb VI and Tauheed et al (1984) Mo VII from our lab, while Khan et al (1981) share the work on Zr V with Reader and Acquista (1979).

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