Emphasizing Historical and Human Dimension of Scientific Discoveries. Using the Example of Nuclear Magnetic Resonance.

1. Emphasizing Historical and Human Dimension of Scientific Discoveries. Using the Example of Nuclear Magnetic Resonance. Mark I. Liff Philadelphia University, Philadelphia, PA, 215-321-4759, liffm@philau.edu

2. Informal Science Education÷Teaching Science to the Public • attention from agencies interested in science education, including the NSF • a story of discovery and development of Nuclear Magnetic Resonance(NMR) • educational and entertaining product. • includes a booklet and software • The Many Faces of Nuclear Magnetic Resonance

3. Why NMR? What is remarkable about it that it deserves to be brought to the attention of the public? A little more than 50 years ago NMR was just an elegant, though not particular important, experiment in the realm of Nuclear Physics. It was not expected to develop into an area of an exceptional scientific significance, nor to have broad practical applications.

4. Who is the public? Who are the people that constitute the target audience? • Why does the public need to know about NMR? What is so unusual, or special about NMR to make it a topic of a common interest? • What are the means to make a story entertaining and, simultaneously, highly educational?

5. NMR today • huge area of science and engineering • continues to develop rapidly in many directions • unrivaled as a structural method • no modern chemical lab without an NMR-spectrometer • and no molecular biology dept or a drug company • in the form of MRI revealed new horizons in diagnostics • changed the way chemists do their work and doctors diagnose their patients • from physics of metals to precise measurements of Earth's magnetic fields, from materials science to archeology archeology

6. the scale of publishing activities involving NMR: • approximately ten books annually • an order of 500 comprehensive reviews • several journals dedicated exceptionally to NMR • thousands of papers in physical, chemical, biological and medical journals containing NMR-data and results obtained by NMR techniques.

7. What is the necessity of bringing science of NMR to the attention of the public? What is remarkable in NMR from a broader point of view, beyond the fact that chemists, biologists, physicists, medical doctors use it extensively? • a unique history of NMR, full of unexpected turns and surprising discoveries • lessons in creativity that can be learned from the pioneers of NMR.

8. history + prehistory ≈ 70 years. • many happy endings, but it had its portion of drama • NMR in liquids and solids has been detected only ≈ 20 years after the theoretical prediction and understanding of the phenomenon. • Due to accidental circumstances NMR was not detected in the 30s, 10 years before Bloch and Purcell • Early experiments--only to verify theoretical models. Nobody thought about applications, especially in chemistry, biology, or medicine.

9. In the fifties, discoveries of chemical shift and spin coupling. Every type of a molecule has its easily recognizable NMR-face. Chemical structure can be read out almost directly from its NMR spectrum • Till the middle 60s NMR was efficient for only one type of nuclei, protons, and only for small molecules. No large molecules. No nuclei like isotopes of carbon, phosphorus, nitrogen, oxygen. No means to improve the situation • Fast Fourier-spectroscopy and computers → NMR of many elements of the Periodic Table • Super-conducting magnets of high homogeneity → NMR of complicated bio-molecules, fragments of proteins and nucleic acids.

10. 1950s--NMR shifted towards chemistry away from physics. • NMR is dead--this was a prevalent diagnosis regarding the physics • 1960s--high-resolution spectra in solid state in the absence of displacement of nuclei with respect to each other. • The train of discoveries continued on: Multidimensional Spectroscopy and Magnetic Resonance Imaging • NMR-industry adopted instantaneously all arriving related technical and theoretical novelties: computer technology, electronics, or cryo-technology, and the concurrent theoretical developments

11. a variety of means to make the story entertaining and educational •   Historical dimension is emphasized •  Human creativity is another focus beyond history • Computer animations to demonstrate the NMR-experiments (absorption, saturation, etc.) • Computer-directed discoveries of Nuclear Overhauser Effect, Chemical Shift, Spin Coupling, etc.

12. 1. Begin from the beginning. • What do an atomic nucleus, a top, and a compass needle have in common? Magnetism and mechanical momentum. • Head-over-heels in the magnetic field. NMR through the eyes of a physicist from the pre-quantum era. • Flip-flopping spins. The quantum-mechanical approach.

13. 2. Against all odds. • Failure as a part of success. What kept Gorter from discovering NMR in 1930s? The role of spin-lattice relaxation. • The roads the lonely spins choose. Resonance experiments with beams of isolated spins by I. Rabi, NY, 1938. • Full speed ahead down the temperature scale. Measurements of spin populations near absolute zero in the late 1930s

14. 3. At the ball of luck and triumph. •    From Russia with discovery. Zavoisky observes electron spin resonance in 1944. •    Born in 1945. NMR is registered by Bloch in Stanford, and Purcell in Harvard. •   The stone that started the avalanche: the discovery of chemical shift in the 1950s. •   Know your neighbor. Spin-spin interactions   • 4. On the way to maturity. • One resonance is fine, two is better. First experiments in double resonance. •    The conductors of spin orchestras. Multiple pulses    • Slender lines and spin gymnastics. Three ways to narrow NMR line-widths. •    Traveling into new dimensions. 2D NMR, nD NMR.

15. Some lessons in creativity from the discoveries in NMR. An attempt to relate the creative strategies that are commonly discussed by creativity experts and trainers with the approaches from the NMR discoveries. • Find What You Are Not Looking For • B. F. Skinner: if you find something unusual and interesting, stop pursuing your original goal, and study in detail the unusual events. • Science classics--Fleming's discovery of penicillin. He was not looking for penicillin.

16. Back to NMR, a great example of finding of what you are not looking for is the discovery of chemical shift in the 1940s and also spin-spin coupling in 1950s. • The physicists tried increased the value of permanent field B to accurately find the magneto-gyric ratio g from a simple formula w = g B. Upon increasing B and homogeneity of the external field B they saw many lines instead of one. Spin coupling was discovered in a similar fashion.

17. Connect The Unconnected, or Look At The Other World. • a classical example: Nicola Tesla's watched a sunset, thinking about the Earth spinning around its axis and originating the idea of an AC motor. • application of the theory developed initially for spin glasses in physics to brain neurons in biomedicine. An approach developed or observed in one world is transferred to another one. • Magnetic Resonance Imaging received a huge momentum after adopting some ideas of Computer Tomography, namely Reconstruction by Projections. • the idea came to MRI from the world of X-rays where information about the image is gained through examining its shadows.

18. NMR/ MRI is totally different from X-rays, there are no shadows in MRI. However application of field gradients in different directions in combination with Reconstruction by Projections. • Looking for examples of successful application of this strategy we can deviate from science • the similar creative approach was used by W. Gordon to develop Pringles potato chips. The question at issue was denser packaging of chips inside the bag • dry chips like dry leaves in the late fall do not pack very closely • wet leaves are rather elastic and can pack closely inside a trash bag. When they dry inside the bag, they retain the shape needed for close packing