I first met Tim when I returned to Ames in 2005. He was the division chief and I was project scientist for SOFIA. Our contact actually intensified once I left for Holland. The director for astronomy and chemistry in the Dutch NSF, NWO, was very interested in starting an astrochemistry network, particularly when I mentioned that we could perhaps links this to the astrobiology efforts at NASA Ames. To hammer this collaborative effort out, he and his colleague made several trips to Ames. One of those trips occurred when, because of political squabbles, congress had called a furlough. This meant that we could not meet at Ames, but Tim arranged that we would, by chance, run into each other at the Stanford Mall and sit down with a cappuccino.  I think this illustrates Tim's pragmatic approach to management well. This was a very successful meeting, likely because it was so casual and relaxed. In passing, Tim mentioned that he considered that NASA would support the efforts at Ames at the tune of 2 million and obviously that was a sign for me to tell NWO that we should support the Dutch effort at the same level and that is what happened. Of course, at that point, Tim turned around and told NASA HQ that they should match the Dutch level of support. As I said, Tim was very pragmatic.

This collaborative framework lead to an intense scientific collaborations between the two of us. Tim was the supervisor of one of my students, Cameron Mackie on a quantum chemistry project on the effects of anharmonicity on PAH spectra. For many years, the three of us had weekly telecoms to discuss progress and future directions. Even after Cameron's graduation and the start of his postdoc, we kept our collaboration on this project and its offshoots going. In fact, we published a paper summarizing the results earlier this year and we had formulated plans for a subsequent paper to be started this fall. Cameron was awarded both the dissertation award of the Laboratory astrophysics division of the American Astronomical Society and of the astrochemistry division of the American Chemical Society. While that is of course mainly to Cameron's credit, in Tim, he had the best possible teacher and mentor in quantum chemistry and Tim was very generous in sharing his insights,  knowledge and expertise.

Over these last 15 years, whenever I was in the Bay Area – and that was often – we would meet in person in my "office" in Mt View – Peets at the corner of Castro and El Camino. We would discuss science and management, but mostly the trials and tribulations of the "life of scientists" in general, sitting in the sun sipping a cappuccino.  The pandemic put a stop to this for a while but we picked it up again earlier this year. As I spend much time in Berkeley, I was looking forward to many more sessions but it is not to be. A very sad moment: My students have lost an excellent teacher and mentor in all things quantum chemistry and I have lost a friend.

I will upload several photo's that come from Cameron and show Tim in full regalia taken during his PhD defense, a very formal occasion. I can only add that this stands Tim well. I also upload a coupe of pictures takes during the discussions with NWO and the various workshops that we organized related to these networks. Notice that Tim has sunglasses at hand in these pictures. In my mind, these sunglasses were by way of trademark: A bit of glamour appropriate for a Californian scientist.