# Martin Karplus

> Austrian-born American theoretical chemist (1930–2024)

**Wikidata**: [Q903471](https://www.wikidata.org/wiki/Q903471)  
**Wikipedia**: [English](https://en.wikipedia.org/wiki/Martin_Karplus)  
**Source**: https://4ort.xyz/entity/martin-karplus

## Summary
Martin Karplus was an Austrian-born American theoretical chemist and biophysicist renowned for his pioneering work in molecular dynamics and nuclear magnetic resonance (NMR) spectroscopy. He was awarded the Nobel Prize in Chemistry in 2013 for developing multiscale models of complex chemical systems, bridging quantum and classical mechanics. His contributions, including the Karplus equation, revolutionized the study of molecular structures and biochemical processes.

## Biography
- **Born**: March 15, 1930, in Vienna, Austria
- **Died**: December 28, 2024
- **Nationality**: Austrian (by birth), American (naturalized)
- **Education**:
  - Harvard College (Bachelor's degree)
  - California Institute of Technology (Ph.D.)
  - University of Strasbourg (postdoctoral research)
- **Known for**: Theoretical chemistry, molecular dynamics, NMR spectroscopy, and the Karplus equation
- **Employer(s)**:
  - Harvard University (Professor)
  - University of Strasbourg (Professor)
  - Columbia University (Professor)
- **Field(s)**: Theoretical chemistry, biophysics, computational chemistry

## Contributions
Martin Karplus made foundational contributions to theoretical chemistry and molecular dynamics:
- **Karplus Equation (1959)**: Developed a relationship between NMR coupling constants and dihedral angles in molecules, enabling the determination of molecular conformations from spectroscopic data. This became a cornerstone of structural chemistry.
- **Multiscale Modeling**: Pioneered methods combining quantum mechanics (for electronic structure) and classical mechanics (for molecular dynamics), allowing simulations of large biomolecules like proteins. This work earned him the Nobel Prize in Chemistry in 2013.
- **CHARMM Software**: Co-developed the Chemistry at Harvard Macromolecular Mechanics (CHARMM) program, a widely used molecular dynamics simulation tool for studying biomolecular systems.
- **NMR Spectroscopy Advances**: Expanded the application of NMR to biological macromolecules, improving the understanding of protein folding and enzyme mechanisms.
- **Publications**: Authored over 1,000 research papers and several influential textbooks, including *Molecular Quantum Mechanics* (with Richard Porter).

## FAQs
**What is the Karplus equation?**
The Karplus equation describes the relationship between the vicinal coupling constants (³J) in NMR spectroscopy and the dihedral angles in molecules. It is expressed as \( J(\phi) = A \cos^2 \phi + B \cos \phi + C \), where \( \phi \) is the torsion angle. This equation is critical for determining the three-dimensional structures of organic and biological molecules.

**Where did Martin Karplus teach?**
Karplus held professorships at Harvard University, the University of Strasbourg (France), and Columbia University. He also conducted research at the California Institute of Technology and was affiliated with the International Academy of Quantum Molecular Science.

**What awards did Martin Karplus receive?**
He received numerous honors, including:
- Nobel Prize in Chemistry (2013)
- Guggenheim Fellowship
- Commander of the Legion of Honour (France)
- Austrian Decoration for Science and Art
- Linus Pauling Award (1987)
- Irving Langmuir Award in Chemical Physics
- Honorary doctorates from the University of Vienna and other institutions.

**How did Karplus's work impact computational chemistry?**
His development of multiscale modeling techniques allowed scientists to simulate large biomolecular systems with unprecedented accuracy. By integrating quantum and classical mechanics, his methods enabled the study of protein dynamics, drug interactions, and enzymatic reactions, advancing fields like structural biology and drug design.

**What is CHARMM, and how is it used?**
CHARMM (Chemistry at Harvard Macromolecular Mechanics) is a molecular dynamics simulation software suite co-created by Karplus. It is used to model the behavior of biological macromolecules, such as proteins and nucleic acids, under physiological conditions. Researchers worldwide rely on CHARMM for studying molecular interactions, folding pathways, and thermodynamic properties.

## Why They Matter
Martin Karplus transformed theoretical chemistry by bridging the gap between quantum mechanics and classical simulations, enabling the study of complex biological systems at atomic resolution. His work laid the foundation for modern computational chemistry and structural biology, influencing fields from drug discovery to materials science. The Karplus equation remains a fundamental tool in NMR spectroscopy, while his multiscale modeling approaches are now standard in biomolecular research. Without his contributions, our understanding of molecular dynamics and protein function would be significantly limited.

## Notable For
- **Nobel Prize in Chemistry (2013)**: Awarded for developing multiscale models for complex chemical systems.
- **Karplus Equation**: A foundational tool in NMR spectroscopy for determining molecular structures.
- **CHARMM Software**: Co-creator of a leading molecular dynamics simulation program.
- **Pioneer in Computational Chemistry**: Integrated quantum and classical mechanics to study biomolecules.
- **Academic Leadership**: Professor at Harvard, Strasbourg, and Columbia; mentor to generations of chemists.
- **Honorary Titles**: Commander of the Legion of Honour, Honorary Citizen of Vienna, and multiple honorary doctorates.
- **Member of Prestigious Academies**: Royal Society, National Academy of Sciences, Austrian Academy of Sciences, and others.
- **Prodigious Research Output**: Authored over 1,000 papers and influential textbooks in theoretical chemistry.

## Body
### Early Life and Education
Martin Karplus was born on March 15, 1930, in Vienna, Austria, into a Jewish family. His father, a physician, and mother, a pianist, fled Nazi-occupied Austria in 1938, settling in the United States. Karplus attended Harvard College, where he earned a bachelor's degree in chemistry. He pursued graduate studies at the California Institute of Technology, completing his Ph.D. under Linus Pauling. His postdoctoral research at the University of Strasbourg (1954–1955) marked the beginning of his lifelong connection to Europe.

### Academic Career
Karplus joined the faculty of the University of Illinois in 1955 before moving to Columbia University in 1960. In 1967, he became a professor at Harvard University, where he spent the majority of his career. Concurrently, he held a professorship at the University of Strasbourg (1979–1996), fostering transatlantic collaboration. His dual appointments allowed him to bridge American and European scientific communities.

### Scientific Breakthroughs
#### Karplus Equation (1959)
In 1959, Karplus derived an empirical relationship between the vicinal coupling constants in NMR spectroscopy and the dihedral angles in molecules. This equation, \( J(\phi) = A \cos^2 \phi + B \cos \phi + C \), became a cornerstone for determining molecular conformations, particularly in organic and biological chemistry. It remains one of the most cited tools in structural analysis.

#### Multiscale Modeling
Karplus's most influential work involved developing multiscale models that combined quantum mechanics (for electronic structure) with classical molecular dynamics (for large-scale motions). This approach allowed researchers to simulate biomolecular systems, such as proteins and DNA, with atomic-level precision. His methods were instrumental in understanding protein folding, enzyme catalysis, and drug-receptor interactions.

#### CHARMM Software
In the 1980s, Karplus co-developed CHARMM (Chemistry at Harvard Macromolecular Mechanics), a molecular dynamics simulation program. CHARMM became a standard tool in computational chemistry, enabling researchers to model the behavior of complex biological systems under realistic conditions. It is widely used in academia and industry for drug design, materials science, and biophysical research.

### Awards and Honors
Karplus received numerous accolades throughout his career:
- **Nobel Prize in Chemistry (2013)**: Shared with Michael Levitt and Arieh Warshel for "the development of multiscale models for complex chemical systems."
- **Guggenheim Fellowship (1965)**: Recognized for his interdisciplinary research in chemistry and physics.
- **Commander of the Legion of Honour (France)**: Awarded for his contributions to French science during his tenure at the University of Strasbourg.
- **Austrian Decoration for Science and Art**: Honored by his native Austria for his scientific achievements.
- **Linus Pauling Award (1987)**: Recognized his outstanding contributions to chemical physics.
- **Irving Langmuir Award in Chemical Physics**: Celebrated his work at the intersection of chemistry and physics.

### Memberships and Affiliations
Karplus was elected to several prestigious scientific academies:
- **National Academy of Sciences (USA)**
- **Royal Society (UK)**
- **Austrian Academy of Sciences**
- **Royal Netherlands Academy of Arts and Sciences**
- **American Academy of Arts and Sciences**
- **International Academy of Quantum Molecular Science**

### Legacy and Influence
Karplus's work revolutionized computational chemistry, making it possible to study biological systems at an atomic level. His multiscale modeling techniques are now foundational in fields like structural biology, drug discovery, and materials science. The Karplus equation remains a standard tool in NMR spectroscopy, while CHARMM continues to be a leading software suite for molecular dynamics simulations. His mentorship of students and collaborators ensured the propagation of his methods across generations of scientists.

### Personal Life and Later Years
Karplus maintained strong ties to both the U.S. and Europe, frequently traveling between Harvard and Strasbourg. He was known for his intellectual rigor, curiosity, and dedication to teaching. In his later years, he continued to publish research and attend conferences, remaining active in the scientific community until his death on December 28, 2024. His contributions have left an indelible mark on theoretical chemistry and computational biology.

## References

1. Integrated Authority File
2. Who's Who in France
3. [Source](https://www.magnifuneralhome.com/martinkarplus)
4. Virtual International Authority File
5. BnF authorities
6. Czech National Authority Database
7. [Le Français Jean-Pierre Sauvage reçoit le prix Nobel de chimie. 2016](https://www.lemonde.fr/sciences/article/2016/10/06/le-francais-jean-pierre-sauvage-recoit-le-prix-nobel-de-chimie_5008910_1650684.html)
8. [The Nobel Prize in Chemistry 2013. Nobel Foundation](https://www.nobelprize.org/prizes/chemistry/2013/summary/)
9. [Table showing prize amounts. Nobel Foundation. 2019](https://www.nobelprize.org/uploads/2019/04/prize-amounts-2020.pdf)
10. Guggenheim Fellows database
11. [Source](http://phys-acs.org/acs-theoretical-chemistry/)
12. [Source](http://geschichte.univie.ac.at/en/persons/martin-karplus-prof-dr)
13. [Irving Langmuir Award in Chemical Physics](https://www.aps.org/programs/honors/prizes/langmuir.cfm)
14. [Source](https://www.aps.org/programs/honors/prizes/langmuir.cfm)
15. Complete List of Royal Society Fellows 1660-2007
16. [Source](https://acspss.org/pauling-medal-award/)
17. [Source](https://www.acs.org/funding/awards/acs-award-for-computers-in-chemical-and-pharmaceutical-research/past-recipients.html)
18. [Source](https://clarivate.com/citation-laureates)
19. Mathematics Genealogy Project
20. International Standard Name Identifier
21. CiNii Research
22. SNAC
23. Encyclopædia Britannica Online
24. Brockhaus Enzyklopädie
25. Munzinger Personen
26. Visuotinė lietuvių enciklopedija Online
27. [Martin Karplus](https://www.magnifuneralhome.com/martinkarplus)
28. [Martin Karplus, lauréat du prix Nobel de chimie en 2013, est mort. 2025](https://www.lefigaro.fr/sciences/martin-karplus-prix-nobel-de-chimie-en-2013-est-decede-20250103)
29. Freebase Data Dumps. 2013
30. Library of Congress Control Number
31. Treccani's Enciclopedia on line
32. LIBRIS. 2018
33. Catalogo of the National Library of India