Reviewing recent progress in the fundamental understanding of the molecule–metal interface, this useful addition to the literature focuses on experimental studies and introduces the latest analytical techniques as applied to this interface. The first part covers basic theory and initial principle studies, while the second part introduces readers to photoemission, STM, and synchrotron techniques to examine the atomic structure of the interfaces. The third part presents photoelectron spectroscopy, high–resolution UV photoelectron spectroscopy and electron spin resonance to study the electronic structure of the molecule–metal interface. In the closing chapter the editors discuss future perspectives. Written as a senior graduate or senior undergraduate textbook for students in physics, chemistry, materials science or engineering, the book?s interdisciplinary approach makes it equally relevant for researchers working in the field of organic and molecular electronics. INDICE: Preface XI List of Contributors XIII 1 Introduction to the Molecule–Metal Interface 1 Nobuo Ueno, Norbert Koch, and Andrew T.S. Wee 1.1 From Organic Semiconductors to Organic Electronic Devices 1 1.2 Role and Function of Interfaces in Organic Electronic Devices 3 1.3 What Will We Learn about the Interfaces? 4 1.4 The Fermi Level and Related Fundamentals 6 1.4.1 Definition of the Fermi Level in this Book 6 1.4.2 Measuring the Fermi Level of Organic Semiconductors 8 1.4.3 The Work Function and the Vacuum Level of a Solid with Finite Size 9 References 13 Part One Theory 15 2 Basic Theory of the Molecule–Metal Interface 17 Fernando Flores and José Ortega 2.1 Introduction 17 2.2 The Molecule Energy Gap Problem: Image Potential Effects 20 2.2.1 Molecule Self–Interaction Energy 20 2.2.2 Image Potential Effects 25 2.3 The Unified IDIS Model: Charge Transfer, Pauli Exclusion Principle (“Pillow”) Effect and Molecular Dipoles 28 2.3.1 The IDIS Model 28 2.3.2 Pauli Repulsion (“Pillow”) Effect and the Unified IDIS–Model 31 2.3.3 Molecular Dipole Corrections and the Unified IDIS Model 34 2.4 DFT Calculations for a Single Molecule on a Surface 35 2.4.1 C60 on Au(111) 35 2.4.2 TCNQ/Au(111) 38 2.4.3 TTF on Au(111) 39 2.5 From a Single Molecule to a Monolayer 42 2.5.1 The Unified IDIS Model for an Organic Ad–layer on a Metal 42 2.5.2 C60/Au(111) 43 2.5.3 TTF/Au(111) 45 2.5.4 More on the Unified IDIS Model 46 References 48 3 Understanding the Metal–Molecule Interface from First Principles 51 Leeor Kronik and Yoshitada Morikawa 3.1 Introduction 51 3.2 A Brief Overview of Density Functional Theory 53 3.3 Electronic Structure of Metal–Molecule Interfaces from Density Functional Theory: Challenges and Progress 59 3.4 Understanding Metal–Molecule Interface Dipoles from First Principles 64 3.4.1 n–Alkane/Metal Interfaces 67 3.4.2 Benzene/Metal Interfaces 68 3.4.3 Pentacene/Metal Interfaces 72 3.4.4 PTCDA/Metal Interfaces 75 3.5 Two Examples of Collective Effects at Metal–Molecule Interfaces 77 3.5.1 Quantum–Confined Stark Effect in Monolayers of Molecules Consisting of Polar Repeating Units 77 3.5.2 Magnetic Molecule/Magnetic Metal Interfaces 79 3.6 Concluding Remarks 81 References 81 Part Two Atomic Structure 91 4 STM Studies of Molecule–Metal Interfaces 93 Swee Liang Wong, Han Huang, Andrew T.S. Wee, and Wei Chen 4.1 Introduction to Scanning Tunneling Microscopy 94 4.1.1 Basic STM Operation 94 4.1.2 Theory of STM 96 4.1.3 Scanning Tunneling Spectroscopy 98 4.2 Factors Affecting Molecular Packing on Perfect Surfaces 100 4.2.1 Molecule–Substrate vs. Intermolecular Interactions 100 4.2.2 Commensurability with Substrate 103 4.2.3 Molecular Density Dependent Phase Transitions 104 4.3 Influence of Inhomogeneity at Metal Surfaces 106 4.3.1 Physical Inhomogeneity at Crystalline Interfaces 106 4.3.2 Surface Electronic States 108 4.3.3 Molecule–Induced Modification of Surface Topography 109 4.4 Manipulation of Molecules Using STM 112 4.5 Summary 116 References 116 5 NEXAFS Studies of Molecular Orientations at Molecule–Substrate Interfaces 119 Dong–Chen Qi,Wei Chen, and Andrew T.S. Wee 5.1 Principles of NEXAFS 120 5.1.1 The X–Ray Absorption Process 120 5.1.2 Molecular Orbitals and Characteristic Resonances in K–shell NEXAFS Spectra 123 5.1.3 Molecular Orientation and Polarization Dependence of the Resonance Intensities 125 5.1.4 Techniques and Instrumentation of NEXAFS 127 5.1.5 Radiation Damage of NEXAFS 129 5.2 Molecular Orientations at Interfaces: the Effect of Molecule–Substrate Interactions 129 5.2.1 Organic/Metal Interfaces 130 5.2.2 Organic/Semiconductor Interfaces 132 5.2.3 Organic/Organic Heterojunction Interfaces 136 5.2.4 CuPc on Other Technologically Important Substrates 139 5.3 Molecular Orientations at Interfaces: the Effect of Strong Intermolecular Interactions 140 5.4 Molecular Orientations of Self–Assembled Monolayers 143 5.5 Summary and Outlook 147 References 148 6 X–Ray Standing Waves and Surfaces X–Ray Scattering Studies of Molecule–Metal Interfaces 153 Alexander Gerlach, Christoph Bürker, Takuya Hosokai, and Frank Schreiber 6.1 Introduction 153 6.2 X–Ray StandingWave Theory 154 6.2.1 General Considerations on Wave Fields in Crystals 154 6.2.2 The Two–Beam Approximation 155 6.2.3 The Darwin Curve 156 6.2.4 X–Ray Absorption and Dipole Approximation 159 6.2.5 The Coherent Position and the Coherent Fraction 161 6.3 X–Ray StandingWave Experiments 162 6.3.1 Beamline Setup at ID32 162 6.3.2 Experimental Details 163 6.4 Examples: Organic Monolayers on Metals 164 References 170 Part Three Electronic Structure 173 7 Fundamental Electronic Structure of Organic Solids and Their Interfaces by Photoemission Spectroscopy and Related Methods 175 Nobuo Ueno, Satoshi Kera, and Kaname Kanai 7.1 Introduction 175 7.2 General View of Electronic Structure of Organic Solids 176 7.2.1 From Single Molecule to Molecular Solid 176 7.2.2 Contribution of Polaron 179 7.2.3 Requirement from Thermodynamic Equilibrium 179 7.3 Electronic Structure in Relation to Charge Transport 180 7.3.1 Ultraviolet Photoemission Spectroscopy 180 7.3.1.1 Energy and Momentum Conservation 180 7.3.1.2 Energy Band Dispersion and Estimation of Band Transport Mobility 183 7.3.1.3 Density of States Effects in Polycrystalline Films 184 7.3.2 Electron Spectroscopy Using Metastable Atom Beam: Characterization of the Molecular Orientation via Wavefunction Spread 186 7.3.2.1 Principle and Characteristics 188 7.3.2.2 Characterization of the Molecular Orientation 189 7.3.2.3 Spatial Wavefunction Distribution of Band Gap States 190 7.3.3 Inverse Photoemission Spectroscopy (IPES) 191 7.3.3.1 Characteristics of IPES 191 7.3.3.2 Comparison between UPS–IPES and Tunneling Spectroscopy 195 7.3.3.3 Comparison with Near–Edge X–Ray Absorption Fine Structure Spectroscopy (NEXAFS) 198 7.3.4 Probing Electron–Phonon Coupling, Hopping Mobility and Polaron by UPS 200 7.3.4.1 Basic Background 200 7.3.4.2 Experimental Reorganization Energy and Polaron Binding Energy 202 7.4 Electronic Structure at Weakly Interacting Interfaces 206 7.4.1 Effects of Inhomogeneity of the Substrate Surface on the Energy Level Alignment 206 7.4.2 Strange Band Bending 207 7.4.3 Radiation Effects on the Energy Level Alignment 208 7.4.4 Mysterious Phenomena: Fermi Level Alignment Issue 209 7.4.4.1 Impacts of Interface Dipole Layer on the Energy Level Alignment 209 7.4.4.2 Impacts of Disorder on the Energy Level Alignment and Band Bending 211 7.5 Summary 213 References 214 8 Energy Levels at Molecule–Metal Interfaces 219 Antoine Kahn and Norbert Koch 8.1 Introduction 219 8.2 The Organic–Electrode Interface 221 8.3 Gap States 223 8.4 Metal Electrodes 228 8.5 Tuning of Charge Injection Barriers 232 8.5.1 Strong Electron Acceptor and Donor Molecules 234 8.5.2 Self–Assembled Monolayers with Dipoles 236 8.6 Conductive Polymer Electrodes 237 References 238 9 Vibrational Spectroscopies for Future Studies of Molecule–Metal Interface 243 Wei–Yang Chou 9.1 Introduction 243 9.2 Selection Rules for Infrared and Raman Spectra 244 9.3 Raman/IR Application in Organic Films 245 References 249 10 General Outlook 251 Norbert Koch, Nobuo Ueno, and Andrew T.S. Wee Index 253
- ISBN: 978-3-527-41060-6
- Editorial: Wiley VCH
- Encuadernacion: Cartoné
- Páginas: 272
- Fecha Publicación: 17/04/2013
- Nº Volúmenes: 1
- Idioma: Inglés