The Invisible Frontier
How the 1987 Solvay Conference Revolutionized Our View of Surfaces
December 14-18, 1987
University of Texas, Austin
Where Giants Gathered to Map the Atomic Landscape
When history's greatest physicists—Einstein, Bohr, Curie—gathered at early Solvay Conferences, they grappled with quantum mysteries that defined modern physics.
By December 1987, another elite group converged in Austin, Texas, for the 19th Solvay Conference, but with a different frontier: surface science. This discipline, crucial for everything from microchips to catalysts, had reached a tipping point. For five days, pioneers like Nobel laureates John Bardeen and Gerhard Ertl debated atomic-scale phenomena at the University of Texas 1 6 .
The conference, edited by physicist F.W. de Wette, captured a revolution: scientists were no longer just theorizing about surfaces but manipulating and imaging atoms directly 1 4 . This article explores how their breakthroughs birthed technologies that shape our world today.
The Solvay Legacy
From quantum mechanics to surface science, Solvay Conferences have shaped scientific history.
Atomic Revolution
The 1987 conference marked the transition from theory to atomic manipulation.
1. The Surface Science Renaissance
Surfaces—where solids meet gases or liquids—are hotbeds of chemical activity. The 1987 Solvay Conference highlighted three transformative areas:
Catalysis Unlocked
Gerhard Ertl (Nobel '07) detailed how reactions like ammonia synthesis occur at specific surface "defects." His work proved that atomic-scale imperfections dictate industrial catalyst efficiency 1 .
The Quantum Interface
Physicist Walter Kohn (Nobel '98) linked surface phenomena to emergent quantum states, foreshadowing today's quantum materials research 6 .
A key theme emerged: surface science had evolved from descriptive studies to predictive control of atomic processes 1 .
1950s-1960s
Early surface science focused on macroscopic measurements
1970s
Development of UHV techniques enabled cleaner experiments
1981
Invention of STM revolutionized atomic-scale imaging
1987
Solvay Conference marked the maturation of surface science
2. The Experiment That Made Atoms Visible: Scanning Tunneling Microscopy (STM)
Background: Before STM, surfaces were studied indirectly. The STM, invented by Binnig and Rohrer (Nobel '86), offered direct atomic imaging. At Solvay, its potential ignited fervent debate 1 6 .
Methodology: A Step-by-Step Journey
The Probe
A platinum-iridium tip sharpened to a single atom is positioned nanometers above a surface.
Quantum Tunneling
A voltage applied between tip and surface drives electrons across the vacuum gap.
Scanning
Piezoelectric crystals move the tip in sub-Ångstrom steps, mapping current variations.
Results and Analysis
Silicon Revolution
Don Hamann's STM work revealed silicon's 7x7 reconstruction—a complex pattern pivotal for semiconductor design.
Catalysis Insights
Jens Nørskov presented STM images of carbon monoxide on platinum, showing how molecules cluster at reactive sites 1 .
Breakthrough Techniques Debated at the Conference
| Technique | Resolution | Key Application | Pioneer (Affiliation) |
|---|---|---|---|
| STM | 0.1 nm | Atomic surface imaging | Binnig (IBM Zurich) |
| Low-Energy Electron Diffraction (LEED) | 1 nm | Surface structure analysis | Lagally (Wisconsin) |
| X-ray Photoelectron Spectroscopy (XPS) | 5 nm | Chemical composition mapping | Siegmann (ETH Zurich) |
3. The Dance of Molecules: Surface Reactions Decoded
Catalysis sessions featured fiery exchanges on how molecules adsorb, diffuse, and react on surfaces:
Dynamic Tracking
Heinz Ibach demonstrated high-resolution electron energy loss spectroscopy (HREELS), proving that surface vibrations dictate catalytic pathways 1 .
Landmark Catalytic Reactions Analyzed
| Reaction | Catalyst | Key Finding | Industrial Impact |
|---|---|---|---|
| Ammonia synthesis (Haber-Bosch) | Iron | N₂ dissociation at step edges | Fertilizer production |
| CO oxidation | Platinum | Langmuir-Hinshelwood kinetics dominate | Automotive catalytic converters |
| Methane reforming | Nickel | Carbon deposition blocks active sites | Hydrogen fuel generation |
4. The Scientist's Toolkit: Essential Research Reagents
Surface science relies on meticulously controlled environments and materials. Key tools featured at Solvay included:
UHV Chamber
Maintains pristine surfaces (pressure ~10⁻¹⁰ mbar)
Prevents surface contamination during STMSingle-Crystal Substrates
Provides atomically flat surfaces
Gold (111) for adsorption studiesMetal Precursors
Deposits pure metal films
Creating model catalystsCalibrated Gas Dosers
Controls exposure to reactive gases
Dosing exact CO amounts onto platinumResearch Reagent Solutions for Surface Experiments
| Reagent/Material | Function | Example Use Case |
|---|---|---|
| Ultra-High Vacuum (UHV) Chamber | Maintains pristine surfaces (pressure ~10⁻¹⁰ mbar) | Prevents surface contamination during STM |
| Single-Crystal Substrates | Provides atomically flat surfaces | Gold (111) for adsorption studies |
| Metal Precursors (e.g., Ni(CO)₄) | Deposits pure metal films | Creating model catalysts |
| Calibrated Gas Dosers | Controls exposure to reactive gases | Dosing exact CO amounts onto platinum |
The Atomic Legacy
The 1987 Solvay Conference wasn't just a meeting—it was a paradigm shift.
As de Wette noted, it forged unity between condensed matter physics and molecular chemistry, enabling technologies from nanoparticle cancer therapies to quantum computing interfaces 1 . The STM, once a novelty, now underpins atomic-scale manufacturing. Catalytic principles debated there guide clean energy solutions.
In essence, Austin became the birthplace of surface engineering—a discipline that continues to turn atomic mysteries into global innovations. As we confront climate change and energy crises, the atomic frontiers mapped in 1987 light our path forward.
The iconic group photo from the conference featured 76 pioneers, including six future Nobel laureates 6 .