Results of experiments on iodine dissociation in active medium of oxygen-iodine laser

Results of experiments on dissociation of iodine molecules in the presence of singlet oxygen molecules are presented for wide range of oxygen-iodine media composition. Rate constants values have been obtained: 4.3⋅10-17cm3/s for the reaction O2(1Δ)+O2(1Δ)→O2(1Σ) +О2(3Σ) − (1), 2.8⋅10-13 cm3/s for the reactionO2(1Δ)+I(2P1/2)→O2(1Σ)+I(2P3/2) − (4) and 8.3⋅10-11 cm3/s for the reaction O2(1Σ) +I2→О2(3Σ)+2I − (2). Analysis of experiments shows that for the wide range of oxygen-iodine medium composition the dissociation occurs via the chain of reactions (1), (2), O2(1Δ)+I(2P3/2)→О2(3Σ)+I(2P1/2), (4) and via cascade process I2+I(2P1/2)→I2(v)+I(2P3/2), I2(v)+O2(1Δ)→2I+О2(3Σ). Contributions of each mechanism in the dissociation of the iodine are comparable for the typical composition of the active medium of the supersonic chemical oxygen-iodine laser. The experiments did not reveal the contribution of vibrationally excited oxygen molecules in the dissociation of iodine. Thus, the experiments and the following conclusions are fully confirmed iodine dissociation mechanism previously proposed by Heidner et al. (J. Phys. Chem., 87, 2348 (1983)).

[1]  K. Waichman,et al.  The I2 dissociation mechanisms in the chemical oxygen-iodine laser revisited. , 2012, The Journal of chemical physics.

[2]  E. A. Ogryzlo,et al.  Some New Emission Bands of Molecular Oxygen , 1964 .

[3]  F. Hovis,et al.  Energy pooling reactions in the oxygen–iodine system , 1984 .

[4]  M. Zagidullin,et al.  Kinetics of formation of O2(1Σ) molecules in reactions involving excited O2(1Δ) oxygen molecules and I(2P1/2) iodine atoms , 2011 .

[5]  U. Schurath.  The energy pooling reaction 2O2(1Δg) → O2(3Σ−g) + O2(1Σ+g; formation, relaxation, and quenching of vibrationally excited O2(1Σ+g) , 1975 .

[6]  R. Derwent,et al.  Measurements on O21Δg and O21Σ+g in discharge flow systems , 1971 .

[7]  M. Zagidullin,et al.  Dissociation of molecular iodine in a flow tube in the presence of O2(1Σ) molecules. , 2012, The journal of physical chemistry. A.

[8]  W. Ubachs,et al.  Visible absorption bands of the (O2)2 collision complex at pressures below 760 Torr. , 1999, Applied optics.

[9]  V. N. Azyazov,et al.  Luminescence of the (O2(a(1)Δ(g)))2 collisional complex in the temperature range of 90-315 K: Experiment and theory. , 2015, The Journal of chemical physics.

[10]  M. Zagidullin.  Nonequilibrium population of the first vibrational level of O2(1Σ) molecules in O2 — O2(1Δ) — H2O gas flow at the output of chemical singlet-oxygen generator , 2010 .

[11]  Experimental and Computational Investigation of a Converging - Diverging Nozzle- Diffuser with Cross Flow Injection , 2010 .

[12]  G. Perram.  Approximate analytic solution for the dissociation of molecular iodine in the presence of singlet oxygen , 1995 .

[13]  G. Fisk,et al.  Rate and efficiency of I2 dissociation in the presence of O2(1Δ) , 1983 .

[14]  C. E. Gardner,et al.  Chain-reaction mechanism for molecular iodine dissociation in the molecular oxygen(1.DELTA.)-iodine atom laser , 1983 .

[15]  T. Slanger,et al.  Collisional relaxation of O2(X3Σg(-), υ = 1) and O2(a1Δg, υ = 1) by atmospherically relevant species. , 2011, The Journal of chemical physics.

[16]  M. Heaven,et al.  Role of O2(b) and I2 (A',A) in Chemical Oxygen-Iodine Laser Dissociation Process , 2006 .

[17]  J. Noxon.  Optical Emission from O(1D) and O2(b 1Σg) in Ultraviolet Photolysis of O2 and CO2 , 1970 .

[18]  P. Houston,et al.  Direct observation of I2 collisional dissociation by O2(b1Σ+g) , 1981 .

[19]  C. E. Gardner,et al.  Temperature dependence of O2(1Δ)+O2(1Δ) and I(2P1/2)+O2(1Δ) energy pooling , 1981 .

[20]  D. Huestis.  Vibrational energy transfer and relaxation in O2 and H2O. , 2006, The journal of physical chemistry. A.

[21]  M. L. Nowlin,et al.  Inelastic collision dynamics of vibrationally excited I2(X) , 1997 .

[22]  R. A. Cox,et al.  Evaluated kinetic and photochemical data for atmospheric chemistry: Volume III - gas phase reactions of inorganic halogens , 2006 .

[23]  V. Azyazov.  REVIEW: Excited states in the active media of oxygen --- iodine lasers , 2009 .

[24]  P. A. Mikheyev,et al.  O2(a1Δ) quenching in the O/O2/O3 system , 2009 .

[25]  Michael C. Heaven,et al.  Kinetic studies for advanced iodine laser concepts , 2003, SPIE LASE.

[26]  R. Collins,et al.  A kinetic study of vibrationally excited O2(a1Δg, ν = 1) by time-resolved absorption spectroscopy in the vacuum ultra-violet , 1972 .

[27]  D. Burde,et al.  Collisional quenching of excited iodine atoms I(5p52P1/2) by selected molecules , 1976 .

[28]  R. Derwent,et al.  The excitation of iodine by singlet molecular oxygen , 1970 .

[29]  V. N. Azyazov,et al.  On the dissociation of I2 by O2(a1Delta): Pathways involving the excited species I2(A'3Pi2u,A3Pi(1u)), I2(X1sigma,upsilon), and O2(a1Delta,upsilon). , 2009, The Journal of chemical physics.

[30]  K. Waichman,et al.  Comparing modeling and measurements of the output power in chemical oxygen-iodine lasers: a stringent test of I2 dissociation mechanisms. , 2010, The Journal of chemical physics.

[31]  W. P. Latham,et al.  Oxygen/Iodine Laser Kinetics and Gain. , 1990 .

[32]  T. Slanger,et al.  Collisional removal of O2(b 1Σg+,v=1,2) by O2, N2, and CO2 , 1998 .

[33]  G. Burns,et al.  Kinetics of Iodine Atom Recombination between 300 and 1164°K , 1971 .