What an October we’ve had so far! A big welcome to our new graduate students Cora, Dayun and Yujing! The office is full to bursting, there’s lots of new science to do, and it’s a very exciting time to be in the lab! And congratulations to Soham for having another singlet fission paper accepted, this one in Angewandte Chemie. Through our ongoing collaboration with Satish Patil, we investigated the role of the acetylene linker that’s such a common motif in acene dimer structures. It definitely comes with a cost, but on balance it looks like an advantage for enhanced triplet production. Take a look!

We put on a good show at the ISPF2 conference in New York this week, with posters from Soham and David, my own invited talk, and a poster and invited talk from our collaborators Kanad Majumder and Satish Patil covering our joint work. And congratulations to Soham for winning a poster award and giving a great last-minute talk!

We’re very excited to have two big papers on singlet fission out this month, inspired by some very insightful measurements by Woojae Kim back when he was a postdoc. In Heterogeneous singlet fission in a covalently linked pentacene dimer (Cell Reports Physical Science) we show how photophysically messy even ‘clean’ dimeric systems can be. The structural heterogeneity we report causes a major headache for spectroscopic analysis, but on the bright side it provides a new handle to steer the dynamics of singlet fission systems from femtosecond to microsecond timescales!

And in a companion study published this week in Nature Chemistry, it looks like the community has been going about singlet fission all wrong for all these years! Turns out that even with a very simple experiment (pump-probe) we can readily directly generate the triplet-pair state without any need for the singlet to first ‘fiss’. This seems like one of the rare mechanistic phenomena that extends from intramolecular to intermolecular fission regimes, suggesting it’s a general property of the TT state. And watch this space – there’s plenty more to come!

It’s summer at last! But a bittersweet one, as we graduate a fantastic group of undergraduate students who are now headed to bigger and brighter things in their PhDs: Pedro – Harvard, Vivian – Maryland, Shamitri – Rochester, Julia – Carnegie Mellon, & Bea – Princeton. It’s been great to work with all of you, and we look forward to your next accomplishments!

We also bid goodbye to Juno, who is returning to Korea for a Research Professor position at Yonsei University. You will be sorely missed!

On the bright side, we have three new undergraduate researchers joining us this week with the Nexus program: Joel, Stephanie, & Ella. Welcome on board!

Big congratulations are in order for this fellowship season! Kiser has been awarded an NDSEG and NSF GRFP, while Pedro has been awarded a GRFP for his graduate work at Harvard and Gloria received an Honorable Mention for her GRFP application. Great work everyone, it was all very well deserved!

Big congratulations to Gloria for her great AEP honor’s thesis work, and we wish her the best on her research at ICFO! To kick off the semester we welcome two new undergraduate students, Guanzhong and Daniel from C&CB – looking forward to working with you!

 

And we had two exciting papers accepted over the break. Aleesha and Trevor’s study of the role of disorder in strong coupling and the (alleged) ultrastrong coupling regime was accepted in the Rising Stars collection of Advanced Optical Materials! Sometimes the simplest description isn’t the best, but we found it can nonetheless be straightforward to account for the significant impact of broadening on the states formed under strong coupling. Hopefully this tool will let us better understand the functional behavior of polaritons!

 

And David and Julia’s investigations of ultrafast quenching dynamics in [3]-cumulenes was accepted in Photochem and highlighted on the homepage. Now we can start to tackle the harder problem of what happens in the solid state!

A lot has happened this semester. First of all a big welcome to our newest PhD student, Yaejin Kim! She’ll be building on her background in spectroscopy from BNL to push forward our studies of ultrafast polariton transport.

The collaboration with the Milner group continues to bear fruit – the CORN-MOF1 paper on fluorescent intermediates in MOF preparation has been accepted at Chemistry of Materials. This paper includes some of the first spectroscopy data ever taken in our labs and was where David and Stavrini cut their teeth. A long time coming, but great work!

 

 

And with a somewhat faster turnaround, Juno has kicked off our collaboration with Qiuming Yu with a beautifully detailed look into polaron dynamics in perovskite quantum dots, just published in ACS Nano. It’s a wonderful example of how spectroscopy should be done!

And finally, our review article on organic exciton-polaritons has just come out at Chemical Physics Reviews. Have a look and learn a thing or two about the problems we face.

Big congratulations to Soham on his first paper in the group, recently accepted in JACS! Part of our long-standing collaboration with Satish Patil (IISc Bangalore), we studied how the full progression of intramolecular SF dynamics can be fine-tuned in pentacene dimers by changing the twist angle between rings within the bridge. Check it out! We’ve got a lot more where this came from…

And a lot of the team – David, Tom, Aleesha, and Suman – have just been carrying the flag for LMG at the Optical Probes conference in Italy. By all accounts, they did a great job. Congratulations, guys!

We are very excited to be starting up three new federally funded projects this Fall: an AFOSR MURI and polariton transport with Russ Holmes (U Minn) and Frank Spano (Temple), a DOE study of photocatalytic materials with Phill Milner, and an NSF project on polariton condensation. Time to get serious in the lab!

We’ve had a lot of great news this semester recognizing some of the team’s excellent work and exciting ideas.

• Suman Gunasekaran was awarded a prestigious Arnold O Beckman Postdoctoral Fellowship in chemical instrumentation – we look forward to working with him for a couple years yet!
• David Bain was awarded the department’s 2023 Howard Neal Wachter Memorial Prize for his outstanding academic and research performance.
• Amy Vonder Haar was awarded a 2023 TA award to recognize her excellent work as a teaching assistant in the department.
• And Ryan Pinard was chosen by the department for the 2023 Darryl H Wu Award for excellence in chemistry.

Congratulations to all of you for your very well-deserved recognition!