Visit to Aix-Marseille University for collaboration with professor Christophe Jouvet 2018.10.31-2018.11.8
I visited the laboratory of professor Christophe Jouvet in Laboratoire de Physique Des Interactions Ioniques et Moléculaires Aix-Marseille University from October 31st to November 8th, 2018 by the support of WRHI. Prof. Jouvet and I are long-term collaborators over 30 years. I met Christophe for the first time when I visited the Université Paris Sud on my way back from the Gordon Research Conference in île d’Oléron in France during my stay in Cornell University. Later, Mitsuo Ito’s laboratory that I was a research associate started collaboration with Laboratoire de photophysique moléculaire du CNRS where Christophe was a researcher, and had chance to work together on spectroscopy of molecular clusters. Since I moved to Institute for Molecular Science, a national research institute in Okazaki via Waseda University, our contact was less frequent, but was restated again when my group studied the excited state hydrogen transfer in phenol-ammonia clusters.
Christophe’s laser laboratory.
Originally people believed that aromatic acids such as phenol changes to strong acid and release a proton (excited state proton transfer) when it is photoexcited. By this reason, phenol, naphthol and related molecules are called “photoacid”. Christophe started to revise this understanding from proton transfer to a neutral hydrogen atom transfer (Excited State Hydrogen Transfer) at the end of 20’s century. Our group provided the definite evidence of excited state hydrogen transfer for the first time and Christophe’s ESHT was established. The establishment of ESHT is “Paradigm Shift” in photochemistry and many photochemical processes including photoprotection mechanism of biomolecules have been interpreted by ESHT. This triggers further collaborations between our group and Christophe, and we have been publishing 13 collaboration papers until now. The purpose of my visit is tight collaboration with Christophe to cowrite the 14th collaboration paper. Topics is EHST in trimer of phenol and two ammonia molecules. Time-resolved experiments has done in TokyoTech and theoretical calculations have been performed by Christophe. We have found double exponential time-evolution of the reaction products which has not been found any other molecular system that has ESHT reaction. In this visit, finally we concluded the two reaction pathways and contribution of triplet reactive electronic states. The contribution of the triplet state is found for the first time in ESHT and I wrote the most of this paper by our conclusion. If you are interested in further scientific part of the collaboration, please read the collaboration paper which will be submitted soon, or contact me.
Marseille is a famous city for sea foods. After finishing discussions on Friday, Christophe took me to a seafood restaurant in the downtown harbor area. The restaurant was operated by a fish store and everyone select the sea foods directly in their stock and enjoyed them with wines. We selected a big plate of oysters and clubs with a bottle of dry white wine, and fully enjoyed fresh sea foods and nice discussion on the collaboration over wine glasses. This was very good refreshments and we got more power on the collaboration.
Friday night, with Christophe at a seafood restaurant.
Finally, I deeply appreciate WRHI and professors Koyama and Azuma for the kind support for the collaboration visit. I believe this direct face-to-face contact enhances more close relation and long-term international collaboration.