Celebrating 100 years of quantum mechanics through IUPAC's special issue
In 2025, the United Nations proclaimed the International Year of Quantum Science and Technology (IYQ), marking the 100-year anniversary of quantum mechanics. This year-long, worldwide initiative aims to increase public awareness of the importance and impact of quantum science on all aspects of life 1 4 .
International Year of Quantum Science and Technology
40 articles in Pure and Applied Chemistry
"Quantum mechanics provides the framework for understanding how atoms and molecules interact with each other. Furthermore, the application of quantum mechanics is crucial for understanding chemical properties, predicting molecular behavior, and developing new technologies in areas like materials science and drug design" 4 .
The evolution of quantum chemistry has been nothing short of remarkable. In 1970, the field published only 600-800 papers per year, with fewer than 400 utilizing advanced ab initio self-consistent field calculations 4 .
Today, the landscape has transformed beyond recognition. By 2024, the number of published articles employing computational modeling techniques had grown to over 177,000 per year. Similarly, molecular dynamics simulations exploded from fewer than 50 papers in 1970 to over 75,000 annually in 2024 4 .
Coupling quantum calculations with atomic motion enabled realistic simulation of reaction mechanisms.
Simulations of bond-breaking/forming processes on the femtosecond timescale (10⁻¹⁵ seconds).
Today's simulations reach the timescale of electronic motion itself (10⁻¹⁸ seconds) 4 .
Molecules with 4-6 atoms represented significant challenges.
Systems with more than 10,000 atoms can be treated computationally using linear-scaling DFT 4 .
Among the many applications of quantum chemistry featured in the PAC special issue, one particularly compelling example comes from battery technology. Researchers have been working to overcome the limitations of aqueous zinc-iodine (Zn-I₂) batteries 2 .
A research team developed a novel iodide-mediated intermediate regulation strategy that significantly enhances battery performance. Their approach involved adding iodide ions (I⁻) to the electrolyte while using an elemental iodine-embedded porous carbon cathode (I₂@PAC) 2 .
Additional iodide ions generate abundant iodine active sites on the cathode surface, facilitating the conversion of under-oxidized triiodide (I₃⁻) to pentaiodide (I₅⁻) 2 .
The iodide-mediated regulation strategy produced remarkable improvements in battery performance:
| Performance Metric | Standard Zn-I₂ Battery | Iodide-Mediated Battery |
|---|---|---|
| Specific capacity at 0.2 A g⁻¹ | ~211 mAh g⁻¹ (theoretical maximum) | 250.2 mAh g⁻¹ |
| Coulombic efficiency | Typically <99% | >99.7% |
| Cycling stability | Limited | 85% capacity retention after 10,000 cycles |
| Zinc deposition morphology | Dendritic | Dendrite-free |
| Iodine Species | Formation Energy in Vacuum (eV) | Formation Energy on I₂@PAC (eV) |
|---|---|---|
| I₅⁻ | -1.52 | -3.05 |
| I₃⁻ | -2.45 | -3.76 |
DFT calculations revealed thermodynamic favorability of I₅⁻ formation on the I₂@PAC substrate 2 .
The zinc-iodine battery experiment illustrates how cutting-edge research often depends on specialized materials and reagents:
Provides high-surface-area substrate for hosting active iodine species, facilitating the I₃⁻ to I₅⁻ conversion.
Serves as dual-source additive providing both Zn²⁺ and I⁻ ions to modulate solvation structure and intermediate regulation.
Embedded in porous carbon cathode to generate abundant active sites for polyiodide transformations.
Base electrolyte component providing the primary source of zinc ions for the electrochemical reactions.
Enables density functional theory calculations and molecular dynamics simulations to predict and explain molecular behavior.
Scanning electron microscopy and energy-dispersive X-ray spectroscopy for material characterization.
The special IYQ issue of Pure and Applied Chemistry represents more than just a collection of scientific papers – it showcases how quantum principles have transformed from abstract theoretical concepts into powerful tools that address pressing global challenges 4 .
"We trust that this issue of PAC will provide a lasting legacy of the state of quantum chemistry in 2025" 4 .
From revolutionizing energy storage to enabling drug design and materials development, quantum chemistry has become indispensable to modern science and technology. As we celebrate 100 years of quantum mechanics, this special issue provides both a reflection on remarkable progress and a glimpse into an even more exciting future.
Smartphones
Modern Medicine
Renewable Energy
For students, educators, and curious minds alike, understanding these quantum principles becomes increasingly essential to comprehending the technological advances that will shape our world in the coming century. The next time you use a smartphone, benefit from modern medicine, or hear about breakthroughs in renewable energy, remember that behind these technologies often lie the fascinating quantum principles that continue to revolutionize our understanding of the molecular world.