ICE Issue 9

36 The Israel Chemist and Chemical Engineer Issue 9 · January 2023 · Tevet 5783 History of Chemistry Articles I am interested in NMR theory, and his immediate response was Shimon Vega! So, this paved the way to carrying out both my MSc and PhD research with Shimon and turned out to be a judicious and gratifying experience. One aspect of working with Shimon on NMR problem solving is the perpetual test of the depth of dive into the theory that one was willing and capable of taking. You can imagine climbing a winding road to a high snowy peak with a cheerful clear-eyed guide always showing up in front of you, restless, at each curve and turn, never tired and always leaping forward two steps ahead, effortlessly. Mind you, you still had to climb up yourself, whether it was writing down the correction terms for finite-pulse XY-8 REDOR using Floquet theory or working out the analytical expressions for matrix diagonalization of homonuclear-coupled spin Hamiltonians. One quality of Shimon which may not strike one immediately as typical of himwas his openness to new ideas and initiatives. We were allowed the time to program a Matlab code for the REDOR transform (which was already proposed by Karl Muel ler at the time) and amused ourselves with possible kernel functions suitable for the other anisotropic interactions. We discussed ways of polarization enhancement and delved into fundamental reasons why an equivalent of stimulated emission population inversion in a MASER in the microwave region was not possible in the radiofrequency region for NMR. However, lengthy digressions from the topic were gently and cleverly discouraged as Shimon was too knowledgeable to allow a complete waste of time. One of the projects, in which I felt that Shimon was caught slightly Shimon wrote many seminal papers when I was still at elementary school, many of them on multiple-quantumNMR using fictitious spin operators. The most influential paper that goes with me everywhere (I still have the yellowed hard-copy, as authors used to get them by mail from the journal) was on triple-quantum excitation of quadrupolar nuclei [3] (see Figure 2). I still think and feel fictitious spin-half operators, and use these tools to understand problems we encounter in our lab. I feel obliged and enthusiastic to always pursue better ways to perform quadrupolar NMR spectroscopy. I try to take from Shimon the patience, the quest for every detail, the devotion to scientific truth and integrity, and the devotion to be there for any eager student, be it your own, or someone else’s. Like all great artists, Shimon’s scientific song and spin art will always be with us. Gil Goobes As an undergraduate student, I had a sense that nuclear magnetic resonance was an exciting field, and probably what I will want to carry out my research on. Professor Gil Navon taught a course on magnetic resonance spectroscopy at that time and was running in parallel a graduate level course on the subject – which I, naturally, joined. Before moving to the Weizmann Institute for my graduate degrees, determined to continue with NMR, I asked the teaching assistant in the graduate course, Itamar Ronen, now Professor at the Leiden University Medical Center, who should be contacted in case Figure 2. Collage of Vega and Naor paper [3].