Progress in SURFACE SCIENCE
VOL. 60, NO. 1_4, 1999
CONTENTS
Six-dimensional quantum dynamics of dissociative 1
chemisorption of Hz on metal surfaces
GEERT-JAN KROES
Erratum 87
PROGRESS IN SURFACE SCIENCE
VOL. 60, NO. 5-6, MARCH-APRIL 1999
Contents
1. Introduction......................................................................................... 92
I.I. Surface superstructures and two-dimensional electron systems. ................ 92
1.2. Surface-state bands .......................................................................... 94
1.2.1. Si(l I l)-7 x 7 and -(SQRT)3 x(SQRT)3-Ag superstructures ................ 94
1.2.2. Electronic structures ............................................................................. 98
Electrical conduction at semiconductor surfaces. ............................................... 102
Fundamentals of electronic transport ................................................................. 102
Free electron model. ..........................................................................................102
Semiconductor statistics.......................................................................................105
Near semiconductor surfaces ................................................................................106
Conduction through surface space-charge layers ................................................... 107
Conduction through surface-state bands .............................................................. 114
Conduction through grown atomic layers .............................................................. 119
Experimental methods ...........................................................................................121
Atomic-structure analysis.......................................................................................121
RHEED................................................................................................................121
SEM ................................................................................................................... 124
STM ...................................................................................................................127
Electronic-state analysis ........................................................................................129
ARUPS ................................................................................................................129
XPS.....................................................................................................................135
Electronic transport measurements .......................................................................137
Four- or six-probe method. ................................................................................ 140
Probe contacts ................................................................................................... 140
Surface conductance ............................................................................................141
Silver adsorption ....................................................................................................142
Ag-induced surface superstructures .......................................................................142
At elevated temperatures ..................................................................................... 142
At lower temperatures ..........................................................................................148
Growth of Ag atomic layers. ..................................................................................153
At elevated temperatures ......................................................................................153
At room temperature............................................................ ................................155
At lower temperatures ..........................................................................................159
Electronic transport................................................................................................161
Surface conductances............................................................................................161
Conductance changes during Ag deposition. ......................................................... 163
On the Si(l 11)-7 x 7 surface ..................................................................................165
On the Si(l 1 1)(SQRT)3 x(SQRT)3-Ag surface ....................................................173
Summary ...............................................................................................................189
Monovalent-atorn adsorptions on Si(lll)-(SQRT)3 x(SQRT)3Ag surface... .............. 189
Noble-metal adsorptions ........................................................................................191
Au adsorption ....................................................................................................... 191
Cu adsorption.........................................................................................................201
Alkali-metal adsorptions ..................................................................................... .. 204
Summary .............................................................................................................. 208
Gold adsorption ................................................................................................... 209
Au-induced surface superstructures. ...................................................................... 209
Phase diagram .......................................................................................................209
x 2-Au superstructure .............................................................................................209
(SQRT)3 x(SQRT)3-Au superstructure ............................. 213
6x 6-Au superstructure ..................................................... 216
Electronic structures ..........................................................217
Valence bands....................................................................217
Band bending ....................................................................219
Electrical conductance ...................................................... 220
On the 7 x 7 clean substrate ..............................................221
On the 5 x 2-Au substrate ..................................................223
On the other substrates ..................................................... 225
Summary .......................................................................... 227
Indium adsorption. ........................................................... 227
In-induced surFace superstructures .................................. 227
On the 7 x 7 clean substrate ..............................................231
Atomic structural evolutions ...............................................231
Electronic-state evolutions ................................................ 237
Electrical conduction ......................................................... 240
On the ^/3 x ^/3-ln substrate ..............................................242
Atomic structural evolutions ................................................ 242
Electrical conduction .......................................................... 245
On the other substrates ........................................................251
Summary ..............................................................................251
Concluding remarks .............................................................251
Acknowledgements............................................................... 252
References............................................................................. 253
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Progress in SURFACE SCIENCE
VOL. 61, NO. 1, MAY 1999
CONTENTS
Laser-induced desorption from STM-selected semiconductor 1
sites
NORIAKI ITOH, JUN'ICHI KANASAKI and JUN XU
______________________________
Progress in SURFACE SCIENCE
VOL. 61, NO. 2-4, MAY/JUNE 1999
CONTENTS
Memoriam 21
STANISLAW OLSZEWSKI
Interaction of slow, very highly charged ions with surfaces 23
T. SCHENKEL, A. V. HAMZA, A. V. BARNES and D.H. SCHNEIDER
PROGRESS IN SURFACE SCIENCE
VOL. 61, NO. 5-6
Contents
1. Introduction............................................................................................. 86
2. General model of metal ............................................................................. 88
3. Quest for stabilization ............................................................................... 94
3.1. Structureless pseudopotential model stabilized jellium ............................. 94
3.2. Ideal metal ........................................................................................ 98
3.3. Structure-averaged jellium ..................................................................... 98
4. Half-space stabilized jellium ...................................................................... 99
4.1. Surface energy....................................................................................101
4.2. Work function ....................................................................................102
4.3. Surface stress ................................................................................. . 103
4.4. Image-plane position ..........................................................................104
5. Sum rules for flat surface of stabilized jellium ......................................... 106
5.1. Hellmann-Feynman sum rules ............................................................ 106
5.2. Stress sum rules. ............................................................................... 108
6. Effect of atomic corrugations .................................................................110
7. Adhesion of two identical metal surfaces. ..............................................114
8. Response of metal surface to external electric field ............................... 116
8.1. Linear response--surface plasrnon dispersion in simple metals.. ......... 118
8.2. Nonlinear response .......................................................................... 120
9. Conclusions ......................................................................................... 122
Acknowledgements................................................................................... 122
References................................................................................................ 123
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Progress in SURFACE SCIENCE
VOL. 61, NO. 7-8, 1999
CONTENTS
Metal deposits on well-ordered oxide films 127
MARCUS BAUMER and HAIMS-JOACHIM FREUIMD
1. Introduction.................................................. 129
2. Experimental details ............................................ 133
2.1. Profile analysis of low energy electron difTraction spots ...... 133
2.2. Scanning tunneling microscopy. ............................... 135
2.3. Transmission electron microscopy. ............................. 140
2.4. Photoelectron spectroscopy .................................. 141
2.5. Infrared spectroscopy ...................................... 143
M. Baumer, H.-J. Freundi Progress in Surface Science 61 (1999) 127-19S 129
3. Substrate: AI^/NiAld 10) ....................................... 144
3.1. Electronic and geometric structure .............. .. ............ 144
3.2. Defects. .............. ................. 149
4. Metal particles: structure and morphology. ...................... 151
4.1. Nucleation and growth at different temperatures............. 151
4.1.1. Rhodium ......................................... 156
4.1.2. Palladium......................................... 159
4.1.3. Cobalt........................................... 162
4.1.4. Platinum ......................................... 165
4.1.5. Vanadium......................................... 167
4.1.6. Comparison and overview ............................. 168
4.2. Thermal stability.......................................... 170
4.3. Growth in ambient gas atmospheres ............................ 172
5. Metal particles: electronic structure. ................................. 174
5.1. Particle size effects. ........................................ 174
5.2. Metal-support interaction ................................... 177
6. Metal particles: adsorption behaviour ................................ 179
6.1. CO adsorption ........................................... 180
6.1.1. Platinum ......................................... 180
6.1.2. Palladium. ...................... 181
6.2. CO dissociation. .......................................... 188
7. Concluding remarks ............................................ 191
Acknowledgements.................................................. 192
References........................................................ 192
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PROGRESS IN SURFACE SCIENCE
VOL. 62, NO. 1-6, SEPTEMBER/NOVEM BER 1999
1. Introduction................................................... 5
2. Morphology of retinal protein-containing membranes ..................... 9
2.1. Purple membrane .......................................... 9
2.2. Visual photoreceptor membranes .............................. 10
3. Structures of retinal proteins ...................................... 11
4. Photochemical reactions of retinal proteins ............................ 15
4.1. Rhodopsin.............................................. 15
4.2. Bacteriorhodopsin......................................... 17
5. Photoelectric effects in pigment-containing membranes. ................... 18
5.1. Light-induced rapid charge displacement. ........................ 18
5.2. Definition of photoelectric effects .............................. 20
5.3. Fast photoelectric signal in reconstituted bR membranes ............. 21
5.4. pH dependence of early receptor potential: apparent paradox? ......... 23
5.5. Mainstream approach ...................................... 28
5.6. Necessity for alternative approach ............................. 28
6. Methods of membrane reconstitution ................................ 31
6.1. Black lipid membranes. ..................................... 32
6.2. Phospholipid vesicles (liposomes) .............................. 35
6.3. Nucleopore-supported films or Collodion films .................... 35
6.4. Immobilized gel technique ................................... 36
6.5. Langmuir-Blodgett technique. ................................ 36
6.6. Takagi-Montal method ..................................... 38
6.7. Trissl-Montal method ...................................... 38
6.8. Multi-layered thin film method................................ 39
7. Electrical measurements of AC photoelectric signals. ..................... 40
7.1. Open-circuit measurement (current clamp method). ................. 40
7.2. Short-circuit measurement (voltage clamp method) ................. 41
7.3. Tunable voltage clamp method. ............................... 41
8. Mechanisms of AC photoelectric effect ............................... 43
8.1. Gouy-Chapman analysis of interfacial proton transfer meclianism . . . . . . 43
8.1.1. Electrostatic calculation. .............................. 47
8.1.2. Kinetic calculation .................................. 52
8.2. Gouy-Chapman analysis of oriented dipole mechanism .............. 53
8.3. Concept of chemical capacitance. .............................. 55
8.4. More refined molecular models. ............................... 56
9. Equivalent circuit analysis of AC photoelectric signals .................... 56
9.1. Strictly short-circuit measurement. ............................. 57
9.2. Measurements under conditions in between short-circuit and open-circuit . 61
9.3. Open-circuit measurement ................................... 63
9.4. Optimizing measurement by tuning access impedance. ............... 66
10. Analysis of AC photoelectric signal from bacteriorhodopsin ................ 66
10.1. Search for method to separate B1 and B2 ........................ 66
10.2. Method for isolating pure B1 signal ............................ 67
10.3. Effect of varying access impedance and thickness of Teflon thin film . . . . . 69
10.4. Temperature effect. ........................................ 72
10.5. Effect of varying aqueous pH and proton-deuterium exchange ......... 75
10.6. Effect of chemical modification. ................................ 78
10.7. Effect of point mutation. .................................... 80
10.8. Chloride ion effect......................................... 82
10.9. Divalent cation effect. ...................................... 86
10.10. Assignment of molecular mechanisms to B1 and B2 components. ....... 89
10.1 1. Q-tip experiment: rationale behind ML method .................... 92
10.12. Method for isolating B2 component ............................ 96
10.13. Evidence of hypothetical B2' component. ........................ 101
10.13.1. Coupled interfacial proton-transfer reactions. ............. 102
10.13.2. Concept of local reaction conditions. ..................... 104
10.13.3. 'Differential' experiment: evidence for existence of B2' ......... 104
10.13.4. Interpretation ofpH dependence of B2 and B2' ............. 106
11. Why is chemical capacitance physically distinct from membrane capacitance?. . . . 108
11.1. Experimental evidence in support of existence of series capacitance ...... 110
1 1.2. Relationship between photovoltage and photocurrent. ............... 114
1 1.2.1. Condition I (open-circuit) ............................. 115
11.2.2. Condition 2 (short-circuit) ............................. 116
1 1.2.3. Interpretation ofTrissVs first-derivative relationship. .......... 116
1 1.3. Additional evidence. ....................................... 117
11.4. Reconciling data reported by other laboratories. ................... 120
12. Analysis of DC photoelectric signal from bacteriorhodopsin. ............... 121
12.1. Equivalent circuit for DC photoelectric effect ..................... 123
12.2. Null current method ....................................... 125
12.3. Null-current analysis of DC photoelectric data .................... 129
12.4. Interpretation of DC photoelectric data ......................... 133
12.4.1. Step-function photoswitching of proton-translocating channel. . . . 133
12.4.2. Interpretation of voltage dependence of photocurrent. ......... 134
12.4.3. Interpretation of spike-like waveform of photocurrent ......... 135
12.5. I-V analysis ............................................. 136
12.6. Effect of ionophores ....................................... 140
12.7. Evaluation of membrane reconstitution methods ................... 140
12.7.1. Orientation of bR molecules ........................... 144
12.7.2. Is bR completely incorporated in a reconstituted membrane? . ... 144
12.8. Mechanism of ionophore action ............................... 149
13. AC photoelectric signal from other pigments ........................... 151
13.1. Early receptor potential ..................................... 152
13.1.1. Direct measurement ofERP in reconstituted membranes ....... 152
13.1.2. Direct assay ofprotonation and deprotonation .............. 154
13.2. AC photoelectric signal from halorhodopsin ...................... 156
13.3. AC photoelectric signals from photosynthetic reaction centers. ......... 157
14. Comparison ofbacteriorhodopsin and pholosynthetic reaction centers. ........ 159
14.1. Photosynthetic reaction center of Rhudopseudomonus viridis ........... 161
14.2. Structurally different systems with similar functional design ........... 162
15. Comparison ofbacteriorhodopsin and rhodopsin. ....................... 166
15.1. Molecular processes of visual transduction ....................... 166
15.2. Why is ERP not necessarily an epiphenomenon? ................... 168
15.3. Effect of surface potential ................................... 170
15.4. Trigger mechanism of visual transduction ........................ 172
15.5. Visual photoreceptor membrane as field-effect transistor. ............. 172
16. Comparison ofbacteriorhodopsin and halorhodopsin. .................... 175
17. Correlation between electrical and optical responses. ..................... 179
18. Retinal protein research and artificial solar-energy conversion. .............. 184
19. Retinal protein research and molecular electronics ....................... 187
19.1. Bacteriorhodopsin as advanced material ......................... 188
19.2. Concept of intelligent materials ............................... 188
19.3. Molecular devices based on photoelectric effect of bR. ............... 191
19.4. Reverse engineering and biomimetic science. ...................... 195
20. Philosophical digression .......................................... 197
20.1. Experimental data, mathematical models and physical models. ......... 198
20.2. Critique on concept of chemical capacitance ...................... 201
20.3. Tentative nature of physical models ............................ 204
20.4. Ockham's razor and Bayesian analysis .......................... 205
20.5. Postdiction, prediction and parsimony .......................... 207
21. Concluding remarks ............................................ 214
Acknowledgements.................................................. 218
Appendix A....................................................... 219
References........................................................ 225
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PROGRESS IN SURFACE SCIENCE
VOL. 62 , NO. 7-8 , 1999
Contents
Introduction 241
Physical models and concepts 244
Pholodissociation and surface-aligned photoreactions on insulators 244
Photochemistry on metals and semiconductors 245
MenzelGomer-Redhead model and its variants 246
Multiple electronic transitions 249
STM induced processes 251
Theoretical methods 252
Classical trajectory methods 252
Time-dependent wavepacket methods 254
Time-dependent Schrodinger equation and its solution 254
Application to photodissociation on insulator surfaces 257
Application to DIET: sudden transition approach 258
Application to DIET: multilevel wavepacket methods 259
Density-matrix methods 260
Liouville-von Neumann equation for reduced denshy operator 261
Solution of Liouville-von Neumann equation 263
Application to DIET problems 265
Application to DIMET problems 267
Time-independent quantum mechanical methods 268
Applications 273
Photodissociation on insulator surlaces 273
DIET dynamics on metal and semiconductor surfaces 275
STM-induced DIET or H (D) From Si 275
DIET of NO 281
DIET of NH(3) 286
DIMET dynamics on metal and semiconductor surfaces 291
Control of DIET and DIMET processes 292
Temperature effects 293
Lifetime variation 294
Pulse parameters 294
Initial state selection 294
Conclusion 295
Acknowledgements 297
References 297
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