41 The Israel Chemist and Chemical Engineer Issue 9 · January 2023 · Tevet 5783 History of Chemistry Articles Daphna Shimon I’m honored to be Prof. Vega’s last PhD student. When I joined his group in 2008, the interest in DNP was seeing resurgence, and I had the great privilege of learning NMR and DNP from Shimon, while also learning DNP together. We spent many hours sitting together trying to understand the experimental data I had accumulated, and to figure out how to model the spin physics of DNP when we could only simulate at most 5–6 spins. There were many days when he would come in the morning and tell me that overnight he had thought of another way we could try and simulate the thing we were looking for. This persistence is something that I always associate with Shimon. He would never give up on trying to understand even the smallest experimental feature. The things I will most remember about Shimon are probably the things many others will remember too: how kind he was, how humble, how good a teacher, and how he always knew problems, like incomplete filling, location of the solution in the extra-porous space, or instability of the MCM-41 structure. In this process, Shimon was a continuous source of critical questions and pertinent suggestions, constantly challenging the interpretation of a phenomenon through the experimental evidence. But Shimon was also a man of great humanity. When SaddamHussein was captured during the second Gulf War, I have a vivid memory of his sense of discomfort as he could not rejoice over the misfortune of any person. Sometimes he shared with me his genuine interest on the people around us, referring either to science or to human relationships. In these small talks, he was sharp and direct, and my personal views were usually in consonance with his, which created a positive and friendly atmosphere. His humbleness still echoes in my mind in the words “there is a whole world out there” that he used to say when he came across some robust and comprehensive study of a subject he had only marginally touched. After 2003 I chose to go back to Italy and life brought me far from the adsorption project started with Shimon. On the contrary, he went on for another ten years investigating different peptides and porous materials. Today my only regret is that I did not continue collaborating with him, although he gave me the chance to do it by giving me samples and a program for simulating MAS spectra in the presence of a two-site motion. Ingolf Sack Shimon was an extraordinary person and outstanding teacher. Perhaps he was the most important teacher for me, with whom I was fortunate to spend a certain period of my life in Israel, at the Weizmann Institute. Shimon had the ability to explain things that loomed only hazily on the horizon of my experimental work in solid-state NMR. This allowed him to predict early on how we would need to design the experiments to accurately determine ²H–13C distances with maximum signal yield. Whether it was the analytic derivation of the Hamiltonian in this specific spin-1 spin1/2 quantum system, or tensor diagonalization in general, Shimon did this with an ease as if it were small talk. Indeed, working with Shimon had the joy, inspiration and ease of a long conversation among friends in which one learns much about the essentials of science and the meaning of life. I am forever grateful to Shimon for the time I was privileged to spend with him, which had a lasting impact on me beyond the realm of science. Figure 3. Shimon Vega’s handwritten explanation of an off-resonant two-level system.