How the 1987 Solvay Conference Charted the Surface Science Revolution
In December 1987, as frigid air swept through Austin, Texas, an intellectual supernova ignited at the University of Texas campus. The 19th Solvay Conference on Surface Science—a gathering historically reserved for physics and chemistry's most existential debates—turned its focus to a then-nascent field: the atomic-scale universe of surfaces. This conference wasn't merely academic; it commemorated the 75th anniversary of the Solvay Institutes, placing surface science in the lineage of quantum revolutions sparked by Einstein and Bohr at earlier Solvay meetings 7 . For five days, 129 pioneers including Nobel laureates John Bardeen (co-inventor of the transistor) and Ilya Prigogine (chaos theory pioneer) debated, clashed, and collaborated to decode nature's most intimate interface—where solids meet the void . Their insights would catalyze breakthroughs from nanotechnology to clean energy.
Surface science emerged from the realization that chemical reactions, electronic behavior, and material stability are dominated by the outermost atomic layers. The 1987 Solvay Conference organized debates around eight pillars that defined the field's frontier 1 7 :
How atoms rearrange to minimize energy, defying bulk symmetry.
The physics of melting, freezing, and ordering in atomically thin layers.
Why platinum speeds reactions, and how to design better catalysts.
Scanning Tunneling Microscopy's (STM) power to visualize atoms.
A core theme was interdisciplinary collision. As noted in proceedings, "physical chemists borrowed quantum theories from physicists; physicists adopted reaction kinetics from chemists" 1 . This fusion birthed predictive models, such as density functional theory (DFT)—pioneered by attendee Walter Kohn—which could simulate surface bond-breaking .
Background: Before STM, surfaces were "seen" indirectly via electron diffraction. Gerd Binnig and Heinrich Rohrer's 1981 invention (Nobel Prize 1986) offered direct atomic visualization—a paradigm shift debated intensely at Solvay '87.
Conference speaker Jene Golovchenko (Harvard) detailed STM's elegant mechanism :
STM images of silicon (111) surfaces revealed the "7×7 reconstruction"—a complex pattern where surface atoms rearranged into a rhombus-like unit cell. This explained silicon's unusual reactivity and paved the way for semiconductor engineering 1 . Attendee Ernst Ruscha (not present but widely cited) noted STM could "resolve bonding orbitals"—not just atoms—enabling chemists to track reactions bond-by-bond.
| Material | Resolution Achieved | Discovery Impact |
|---|---|---|
| Silicon (111) | 0.1 nm (atomic) | 7×7 reconstruction mechanism |
| Platinum (110) | 0.2 nm | CO oxidation active sites mapped |
| Graphite | 0.3 nm | Charge density waves visualized |
| Element | Binding Energy (eV) | Surface Sensitivity | Catalytic Relevance |
|---|---|---|---|
| C 1s | 284.8 | 1–3 atomic layers | Coke formation on catalysts |
| O 1s | 530.1 | 1–2 atomic layers | Oxide formation/activation |
| Pt 4f | 71.2 | 0.5–1 atomic layer | Active site quantification |
| Technique | Probe | Depth Analyzed | Lateral Resolution | Key Solvay Topic |
|---|---|---|---|---|
| STM | Tunneling current | 0.3 nm | 0.1 nm | Atomic reconstruction |
| LEED | Electron diffraction | 1–3 nm | 1 μm | Surface periodicity |
| Synchrotron XPS | X-rays | 0.5–5 nm | 10 μm | Chemical bonding |
Critical materials and methods featured in Solvay discussions 1 :
Atomically flat substrates for controlled studies
Example: Pt(110) for CO oxidation catalysis
High-intensity X-rays to excite core electrons
Example: Probing bonding states in adsorbed molecules
Gas-phase reactants for surface deposition
Example: Trimethylaluminum for aluminum oxide films
Maintain surface cleanliness (10⁻¹² bar)
Example: Preventing contamination during STM scans
The 1987 Solvay Conference crystallized surface science as a discipline where theory met experiment at the atomic scale. Its debates presaged today's nano-revolution:
As F.W. de Wette, conference chair, noted: "Surfaces are where materials negotiate with the world." Thirty-eight years later, that negotiation has birthed quantum computers, molecular factories, and atomic-scale medicine—proof that when giants gather at the frontier, they redraw the map of the possible 5 7 .