Electronic and Ionic Impact Phenomena III

Massey H.S.W., Burhop E.H.S., Gilbody H.B.2-2028-2030-2

Table of contents :
Title page ……Page 1
Date-line ……Page 2
PREFACE TO THE SECOND EDITION ……Page 3
PREFACE TO THE FIRST EDITION ……Page 5
ACKNOWLEDGEMENTS for VOLUME III ……Page 7
CONTENTS ……Page 9
1. Introduction—classification of possibilities ……Page 19
2. General nature of the interaction between atoms ……Page 22
3.1. Cross-sections effective in scattering, viscosity, and diffusion ……Page 25
4. Quantal and classical cross-sections for rigid spherical atoms ……Page 28
4.1. The effect of symmetry ……Page 32
5.1. Classical formulae ……Page 33
5.1.1. Orbiting ……Page 34
5.1.4. Example ……Page 36
5.1.6. Small-angle scattering ……Page 39
5.2. Relation of classical to quantal formulae ……Page 41
5.3. Semi-classical approximation ……Page 43
5.3.1. Glory interference effects ……Page 44
5.3.2. Interference effects near the rainbow angle ……Page 45
5.4. Quantum theory of scattering by long-range potentials ……Page 46
5.4.1. The total cross-section for potentials varying as $r^{-s}$ ……Page 47
5.4.2. Small-angle scattering for potentials varying as $r^{-s}$ ……Page 49
5.4.3. The effect of glory scattering ……Page 50
5.4.4. Orbiting under quantum conditions ……Page 53
6.1. Analytical representations of interatomic interactions ……Page 57
6.2. Reduced parameters when the semi-classical approximation is valid ……Page 59
6.3. Cross-sections in terms of reduced parameters ……Page 61
6.3.1. The low- and high-velocity regions ……Page 62
6.4. Dependence of the rainbow angle on interaction parameters ……Page 63
6.6. Determination of potential parameters from experimental data ……Page 64
7.1. The production and detection of molecular beams ……Page 66
7.2.1. The principle of the method ……Page 70
7.2.2. Angular resolution ……Page 73
7.2.3. Typical experimental arrangements ……Page 75
7.2.3.1. The use of velocity selectors ……Page 79
7.3. The crossed-beam method for measuring total cross-sections ……Page 85
8. The measurement of differential cross-sections ……Page 90
9.1. The classical approximation and its failure at very small scattering angles ……Page 93
9.2. The velocity variation of the total cross-section ……Page 97
9.2.1. The asymptotic form of the interaction ……Page 99
9.2.2. The ‘glory’ oscillations ……Page 101
9.3. Absolute measurement of cross-sections—determination of the van der Waals constant G ……Page 105
9.3.1. Comparison with calculated values ……Page 110
9.4.1. Analysis of observations of rainbow effects ……Page 111
9.4.2. Further experiments at high resolution ……Page 113
9.5. Self-consistency of data derived from different types of experiment ……Page 120
10. The interaction between helium atoms at large and intermediate separations ……Page 123
10.1. The low-temperature evidence (T < 20 °K) ……Page 124
10.2. Results from observations of transport properties and second virial coefficients for T > 20 °K ……Page 132
10.3. Measurement of the total cross-section for He-He collisions ……Page 135
11. Interactions between other pairs of rare-gas atoms ……Page 137
12.1.1. Formulae for the cross-sections ……Page 142
12.1.2. The H-H interactions ……Page 143
12.1.3. The total elastic cross-sections for H-H collisions ……Page 145
12.1.4. The viscosity of atomic hydrogen ……Page 148
12.2.1. Experimental method ……Page 153
12.2.2. Analysis of data ……Page 155
12.3. The viscosity and thermal conductivity of atomic oxygen ……Page 157
12.4. Observation of the anisotropy of van der Waals forces ……Page 160
12.4.1. The magnitude of the effects expected ……Page 161
12.4.2. The experimental method ……Page 163
12.4.3. The observed results ……Page 166
13.1. Special features associated with such collisions ……Page 168
13.2. Collisions of K and Cs atoms with various molecules ……Page 170
13.3. Collisions between dipolar molecules and other (non-polar) molecules ……Page 173
13.4. The H-H2 interaction ……Page 176
13.5. The H2-H2 interaction ……Page 177
13.5.1. The mean interaction—evidence from transport and total cross-sections ……Page 178
13.5.2. The anisotropic component of the interaction ……Page 181
13.6. Interaction of H2 molecules with rare-gas atoms ……Page 185
1. Introductory remarks concerning the probability of vibrational and rotational transitions in gas-kinetic collisions ……Page 187
2.1. The dispersion and absorption of high-frequency sound ……Page 190
2.1.2.1. The ultrasonic interferometer ……Page 194
2.1.2.2. Further methods for measurement of sound absorption ……Page 197
2.1.3. Some notes on the derivation of relaxation times from measurements of ultrasonic dispersion and absorption ……Page 199
2.2.1. Principles of the shock tube and its application to relaxation measurements ……Page 200
2.2.2. Measurement techniques ……Page 207
2.2.3. Optical techniques for temperature measurement ……Page 211
2.3. The effect of persistence of vibration in gas dynamics ……Page 215
2.4. Spectroscopic methods for measurement of vibrational relaxation time for molecules in ground electronic states ……Page 220
2.4.1. The quenching of infra-red fluorescence ……Page 221
2.4.2. The use of flash spectroscopy ……Page 226
2.5. Spectroscopic methods for measurement of vibrational relaxation times for molecules in excited electronic states ……Page 228
2.5.1. The use of laser-induced fluorescence ……Page 232
2.6. The spectrophone ……Page 235
3.1.1. Pure diatomic gases ……Page 242
3.1.2. Mixtures of diatomic molecular gases with rare gases ……Page 246
3.1.3. Pure polyatomic gases and mixtures with rare gases ……Page 247
3.1.4. The effect of diatomic and polyatomic impurities on the vibrational relaxation times of molecular gases ……Page 256
3.2. Relaxation times for higher vibrational levels ……Page 261
3.3. Summarizing remarks ……Page 262
4.1.1. Application of distorted-wave method with exponential interaction ……Page 264
4.1.2. Temperature dependence of deactivation probability ……Page 267
4.1.3. Semi-classical method ……Page 268
4.2. Head-on collisions between diatomic molecules, with exponential interaction—vibrational transfer ……Page 269
4.3. Use of a more realistic interaction ……Page 271
4.4.1. Semi-empirical treatment ……Page 274
4.4.2. Application of the close-coupling (truncated eigen-function) method ……Page 277
4.5. Elementary theory of vibration-rotation transfer ……Page 285
4.6. Summarizing remarks on the theory of vibrational relaxation ……Page 287
5. The excitation and deactivation of molecular rotation on impact between molecules ……Page 288
5.1. Observed rotational relaxation in H2 and D2 ……Page 289
5.2. Theoretical calculation of rotational relaxation times for H2, D2, and HD ……Page 290
5.3. Rotational excitation of H2 and of D2 by collision with H and with He atoms ……Page 300
5.4.1. Experimental evidence from acoustic and shock-wave observations ……Page 301
5.4.2. Rotational relaxation and thermal conductivity of gases ……Page 303
5.4.2.1. Rotational relaxation from measurements of thermal transpiration ……Page 306
5.4.3. Spectroscopic evidence ……Page 307
5.5.1. Theoretical considerations ……Page 312
5.5.2. Experiments on the scattering of beams of polar molecules in selected rotational states ……Page 317
5.5.2.1. Dependence of elastic cross-section on molecular orientation ……Page 319
5.5.2.2. Collisions involving rotational transitions ……Page 323
5.6. Theoretical discussion of collisions between polar molecules ……Page 330
5.6.1. Comparison with observation ……Page 336
5.7. Resonant transfer of rotational energy and the thermal conductivity of polar gases ……Page 339
5.8. Collisions involving change of molecular orientation only ……Page 340
6.1. Introduction ……Page 346
6.2. The determination of the total reaction cross-section—relation to non-reactive scattering—complex phase shifts ……Page 348
6.3. Experimental analysis of angular, recoil, and internal energy distribution in the reaction K+Br2 -> KBr + Br ……Page 358
6.4. Results for reactions of alkali atoms with other halide molecules ……Page 367
6.5. The use of ionization detectors in the study of reactions between crossed molecular beams—the reaction of D with Br2 ……Page 370
6.6. Concluding remarks ……Page 372
1. Introduction ……Page 375
2.1. Quenching experiments with resonance radiation ……Page 377
2.1.1. Quenching experiments with flame gases ……Page 380
2.1.2. Quenching cross-sections from lifetime measurements ……Page 386
2.1.3. Quenching cross-sections from the rate of decay of imprisoned resonance radiation ……Page 387
2.2. Use of flash photolysis and time-resolved spectroscopy ……Page 390
2.3. Deactivation of atoms excited by shock waves ……Page 394
2.4. Deactivation of excited atoms produced by optical dissociation ……Page 399
2.5. Deactivation of Hg($6^3P_1$) and Hg($6^3P_0$) ……Page 400
2.6. Deactivation of Hg($7^3S_1$) and Hg($6^3D_1$) ……Page 415
2.7. Preliminary discussion of results on quenching cross-sections ……Page 416
3.1. Introduction—the disorientation and disalignment cross-sections ……Page 420
3.2. Principles of the method of measurement of disorientation and disalignment cross-sections for atoms with no nuclear spin using Hanle effect ……Page 424
3.3. Experimental measurement of cross-sections ……Page 427
3.4. Double resonance method ……Page 435
3.5. Depolarization of Hg($6^3P_2$) ……Page 439
3.6. Depolarization of atoms excited by step-wise excitation ……Page 441
3.7. Effect of nuclear spin ……Page 443
3.8. The measurement of cross-sections for self-depolarization ……Page 446
3.9. Depolarizing cross-sections for neon ……Page 449
3.10. Depolarization of rubidium and caesium resonance radiation ……Page 453
4. Sensitized fluorescence ……Page 455
4.1.1. Collision-induced transitions between $^2P_{1/2}$ and $^2P_{3/2}$ states of alkali-metal atoms ……Page 458
4.1.2. The excitation of fine-structure transitions in other atoms ……Page 463
4.1.3. Cross-sections for ‘mixing’ collisions between the fine-structure levels of He($2^3P$) ……Page 464
4.2.1. Introduction ……Page 467
4.2.2.1. Mercury-sensitized sodium fluorescence ……Page 468
4.2.2.2. Mercury-sensitized indium fluorescence ……Page 473
4.2.2.3. Mercury-sensitized thallium fluorescence ……Page 474
4.2.2.4. The enhancement of spark lines ……Page 479
4.2.3. Wigner’s spin-conservation rule ……Page 480
4.2.3.1. Transfer collisions in helium—apparent breakdown of Wigner’s rule ……Page 481
4.2.3.2. Transfer collisions in helium—importance of transfer through F states ……Page 482
4.2.3.3. Transfer collisions in helium—application of time-resolved spectroscopy ……Page 485
5. Collisions involving metastable atoms ……Page 491
5.1.1. Measurement of total cross-sections ……Page 493
5.1.2. Discussion of results ……Page 494
5.1.3. Measurement of differential cross-sections ……Page 498
5.2.1. Introduction ……Page 500
5.2.2.1. Helium ……Page 504
5.2.2.2. Neon ……Page 507
5.2.2.4. Effect of impurities ……Page 516
5.2.2.5. Excitation transfer between metastable helium and normal neon atoms ……Page 520
5.2.3. Metastable atoms in flowing afterglows ……Page 523
5.2.4.1. Helium and neon ……Page 525
5.2.4.2. Mercury ……Page 530
5.2.4.3. Effect of impurities ……Page 533
5.3.1. Enhancement by metastable atoms of ionization produced by alpha particles ……Page 534
5.3.2. Measurement of cross-sections using metastable atom beams ……Page 539
5.3.3. The energy distribution of the electrons produced by Penning ionization ……Page 541
5.3.4. Discussion of results ……Page 545
5.4.1. Lower limits from beam experiments ……Page 546
5.4.2. Optical-pumping method ……Page 547
5.5.1. Introduction ……Page 552
5.5.2. Experimental methods and results for quenching of O($^1S$) ……Page 555
5.5.3. Excitation of O($^1S$) in three-body recombination ……Page 562
5.5.4. The quenching of metastable O($^1D$) ……Page 563
6.1. Introduction ……Page 565
6.2.1. From the relaxation time of a hyperfine population ……Page 568
6.2.2. Use of optical pumping to Zeeman levels ……Page 575
6.2.3. Nuclear magnetic-resonance method ……Page 578
6.2.4. Stimulated emission method ……Page 582
6.2.5. Use of the hydrogen maser ……Page 585
7. Spin-reversal collisions ……Page 588
8. Collisions involving excited atoms—discussion and theoretical interpretation of results ……Page 592
8.1.1. Symmetrical and accidental resonance ……Page 593
8.1.2. The case of symmetrical resonance ……Page 594
8.1.3. Application to collisions of metastable helium atoms in helium ……Page 600
8.1.3.1. The deactivation of He(2$^1S$) in collisions with normal He atoms ……Page 603
8.1.4. Application to transfer of excitation on impact between hydrogen atoms ……Page 605
8.2. Collisions in which $Delta E = 0$—spin-exchange collisions ……Page 608
8.2.1. Spin-exchange collisions between H atoms ……Page 609
8.2.2. Spin-exchange collisions between alkali-metal atoms ……Page 612
8.2.3. Spin-exchange collisions between H and O atoms ……Page 614
8.3. Collisions in which $Delta E = 0$—collisions producing depolarization ……Page 616
8.3.1. Collisions between atoms of the same electronic structure ……Page 618
8.3.2. Collisions between atoms with different electronic structure ……Page 625
8.3.3.1. Self-depolarization of $^3P_1$ levels ……Page 626
8.3.3.2. Depolarization of $^3P_1$ levels in collisions with foreign atoms ……Page 629
8.3.4. Depolarization of states of integral J other than $^3P_1$ ……Page 630
8.3.4.2. Hg($6^1P_1$) ……Page 631
8.3.4.4. Hg($6^3D$) and Hg($6^1D$) ……Page 632
8.3.5. Inclusion of nuclear spin ……Page 633
8.3.6. Impact disorientation and disalignment of atoms in excited states with $J = 1/2$ or 3/2 ……Page 636
8.4. Collisions in which the resonance is imperfect ($Delta E neq 0$) ……Page 638
8.4.1. The crossing-point case ……Page 639
8.4.2. The case of no crossing point ……Page 642
8.4.3. Unsymmetrical or accidental resonance ……Page 647
8.4.4. Summarizing remarks ……Page 648
8.4.5. Collisions in which transitions occur between fine-structure levels ……Page 649
8.5. Collisions in which electron spin-flip occurs ……Page 652
8.6. Remarks on collisions involving molecules in which electronic transitions occur ……Page 653
1. Introduction ……Page 656
2.1. Introductory remarks ……Page 657
2.2.1. The electrical-shutter method ……Page 660
2.2.2. Hornbeck’s method ……Page 662
2.2.3. The pulse method of Biondi and Chanin ……Page 666
2.2.4. Parallel-plate method ……Page 668
2.2.5. Mobilities derived from electron decay measurements in afterglows ……Page 675
2.2.6. Cyclotron-resonance method ……Page 678
2.3. Observed mobilities for the alkali-metal ions in rare gases ……Page 681
2.4. The theory of the mobility of ions in non-reacting gases ……Page 682
2.5. Mobilities of alkali-metal ions in molecular gases ……Page 688
2.6. Mobilities of NO+ ions in He, Ar, H2, and N2 ……Page 689
3.1.1. The clustering of water molecules ……Page 690
3.1.3. Theory of ion clustering ……Page 692
3.2.1. The mobility of helium ions in helium—historical account ……Page 696
3.2.2. The mobility of helium ions in helium—experimental techniques andresults at 300° K—drift-tube measurements ……Page 699
3.2.3. The mobility of helium ions in helium—experimental techniques and results at 300° K—afterglow observations ……Page 706
3.2.4. The mobility of helium ions in helium—experimental techniques and results at 300° K—determination of atomic to molecular ion conversion rate by measurements of the optical emission from an afterglow ……Page 711
3.2.5. The mobility of helium ions in helium—experimental results at temperatures below 300° K ……Page 714
3.2.6. The mobilities of other rare-gas ions in their parent gases ……Page 718
3.2.7. The mobility and reactions of Hg+ ions in mercury vapour ……Page 720
3.3. The theory of the effect of charge transfer on the mobilities of ions in their parent gases ……Page 721
3.3.1. Applications to H+ in H and D+ in D ……Page 723
3.3.2. Application to He+ ……Page 724
3.3.3. Application to other atomic ions in their parent gases ……Page 725
3.3.4. Mobilities of diatomic ions in their parent (atomic) gases ……Page 726
3.4. Mobilities of positive ions in their parent (diatomic) gases—ionic reactions in general—experimental methods ……Page 727
3.4.1. Use of a mass spectrograph without a drift tube ……Page 728
3.4.2. The associated drift tube and mass-spectrometer technique ……Page 736
3.4.3. Drift tube combined with inlet and exit mass analysis ……Page 739
3.4.4. Static afterglow studies using mass spectrographs ……Page 742
3.4.5. The flowing-afterglow method ……Page 745
3.5.1. Hydrogen ions in hydrogen ……Page 752
3.5.2. Nitrogen ions in nitrogen ……Page 760
3.5.3. Ions in oxygen and in helium-oxygen mixtures ……Page 767
3.5.4. Ions in nitrogen-helium mixtures ……Page 775
3.5.6. Ions in nitrogen-oxygen mixtures ……Page 776
3.5.7. Reactions of nitrogen and of oxygen ions with nitric oxide ……Page 784
3.5.8. Summary of results for reactions of helium, nitrogen, and oxygen ions with N2, O2, NO, N, and O ……Page 785
3.5.9. Reactions of nitrogen and of oxygen ions with CO and CO2 ……Page 786
3.5.11. Reactions of Ar+ ions ……Page 787
4. Reactions involving negative ions ……Page 788
4.1. Mobility of negative ions in oxygen ……Page 789
4.2.1. Introduction ……Page 807
4.2.2. Adaptation of the pulse method ……Page 809
4.2.2.1. Analysis of the low-pressure data in O2 ……Page 812
4.2.2.2. Analysis of the high-pressure data in O2 ……Page 815
4.2.2.3. Experimental results in O2 and their interpretation ……Page 816
4.2.2.4. Attachment and detachment rates in oxygen at high $F/p$—detachment from O- ……Page 820
4.2.3. The rates of associative detachment reactions ……Page 825
4.3. Charge transfer reactions involving negative ions at thermal energies ……Page 829
4.4.1. Negative ions in CO2 and in O2-CO2 mixtures ……Page 830
4.4.2. Ions in H2O and in O2-H2O mixtures ……Page 834
4.5. Notes on the theory of detachment reactions ……Page 837
Fig. 17.7 ……Page 839
Fig. 17.8 ……Page 840
Fig. 17.11 ……Page 841
Fig. 17.22 ……Page 842
Fig. 17.23 ……Page 843
Fig. 18.10 ……Page 844
Fig. 18.16 ……Page 845
Fig. 18.106 ……Page 846
AUTHOR INDEX ……Page 847
SUBJECT INDEX ……Page 858