Monday • Tuesday • Wednesday • Thursday • Friday

Wednesday, June 16

All times in Eastern Daylight Time (GMT-4)

Chair: Tullio Scopigno, University of Rome

9:00 - 9:30 am | Minhaeng Cho, Korea University, Republic of Korea

Vibrational SFG study of graphene wettability and time-variable SFG spectroscopy of chiral chemical solutions

Using vibrational sum-frequency-generation spectroscopy of interfacial water, we studied graphene wettability and hydrophobicity. We found a spectroscopic signature of non-H-bonded water hydroxyl groups at the graphene-water interface, which reveals the structure of the water H-bonding network on an atomically thin graphene layer on a solid substrate.

9:30 - 10:00 am | Jan Helbing, University of Zürich, Switzerland

Time resolved structure from local coupling changes – a pledge for transient CD and UV-labelling

Coupling changes between amide I transition dipoles are weak and often hidden by the high sensitivity of individual vibrators to their environment. We explore if backbone conformational change can be better resolved when thio-substitution creates spectrally isolated, coupled UV-transition dipoles that are studied by broad band absorption and CD spectroscopy.

The talk originally scheduled for this time slot has been moved to Thursday morning (8:40 - 9:00 am) due to a flight delay for the speaker’s plane.

10:00 - 10:35 am | Break

10:35 - 11:05 am | Huib Bakker, AMOLF, The Netherlands

Femtosecond Vibrational Spectroscopy of the Molecular Interactions and the Dynamics of Water in Supramolecular Hydrogels

We study the molecular mechanism of the formation of supramolecular hydrogels with two-dimensional and polarization-resolved femtosecond vibrational spectroscopy. We investigate the nature of the hydrogen bonds between the polymer chains of the gel-forming ubiquitous polysugar hyaluronan, and the effect of gel formation on the reorientation dynamics of the water molecules embedded in the hydrogel. These latter dynamics provide surprising new insights in the formation mechanism of the hydrogel.

11:05 - 11:35 am | Thomas la Cour Jansen, University of Groningen, The Netherlands

Resolving Islet Amyloid Polypeptide Fibril Structures with Time Resolved Vibrational Spectroscopy

We present simulated spectra of pristine and isotope-labeled amide-I’ vibrations for three proposed structures of the islet amyloid polypeptide. We propose distinct fingerprints to identify the three structures and compare with reported experimental data.

11:35 - 11:55 am | Sophia Hayes, University of Cyprus, Cyprus

Excited state dynamics of a conjugated polyelectrolyte self-assembled with ss-DNA

We employed time-resolved IR spectroscopy to unveil the photophysics of a cationic polythiophene when complexed to ss-DNA, which templates the molecular conformation of the polymer through non-covalent interactions. Selective excitation of the polymer and the DNA chains reveals the photoexcited species responsible for the modified dynamics upon interaction.

11:55 - 12:10 pm | Break

Chair: Ellen Backus, University of Vienna

12:10 - 12:40 pm | Paul Donaldson, Rutherford Appleton Laboratory, UK

2D-IR-Raman spectroscopy of the amide I band

This talk explores recent approaches that combine IR and Raman processes in homodyne and heterodyne 2D and photon echo measurements. The close links between these measurements and approaches of 2D-IR spectroscopy will be discussed and experimental illustrations will be presented via measurements of the amide I band of proteins.

12:40 - 1:10 pm | Karin Hauser, University of Konstanz, Germany

Unravelling the unique role of glutamine dynamics in disease-related aggregation

Polyglutamine (polyQ) diseases are caused by aggregation of expanded polyQ repeats in the affected protein. To understand the aggregation onset, we monitored glutamine-specific sub-millisecond structural dynamics by a combination of appropriately tailored polyQ model peptides and infrared (IR) detected laser-excited temperature-jump spectroscopy.

1:10 - 1:30 pm | Karsten Heyne, Free University of Berlin, Germany

Proton coupled electron transfer: A new mechanism for phytochrome photoisomerization?

Phytochromes exhibit two different photoisomerization processes within nearly identical proteins. The Pfr photoreaction occurs within 1-2 ps. In phytochromes from Agrobacterium fabrum we observe proton transfer to the protein water moiety in the electronic excited state. We discuss PCET as a general mechanism for Pfr photoreaction in phytochromes.

1:30 - 1:45 pm | Break

1:45 - 2:15 pm | Renee Frontiera, University of Minnesota, USA

Probing plasmon-mediated chemistry with ultrafast SERS

We developed ultrafast surface-enhanced Raman spectroscopy to probe energy flow in coupled plasmon-molecule systems. Plasmonic nanomaterials are promising photocatalysts due to their ability to concentrate electromagnetic fields, generate electrons and holes, and serve as localized heat sources. We use ultrafast SERS to track molecular dynamics in this unique plasmonic environment.

2:15 - 2:35 pm | Mahima Sneha, Rühr-University Bochum, Germany

Structure and Solvent Dependent Photophysics of Organic Photoredox Catalysts

In this study, photodynamics of organic catalysts used in photoredox catalysis were investigated using time resolved vibrational and electronic spectroscopies. Effects of structural modifications and different solvent environments on the singlet and triplet lifetimes and intersystem crossing efficiencies were explored to gain insight on the structure-function dynamics of these catalysts.

2:35 - 2:50 pm | Break

Chair: TBA

2:50 - 3:20 pm | Megan Thielges, University of Indiana, USA

Site-selective Infrared Spectroscopy to Investigate Protein Conformations and Dynamics

We combine the inherent temporal resolution of linear and two-dimensional infrared spectroscopy with the spatial resolution afforded by site-selective incorporation of vibrational reporter groups with frequency-resolved absorptions toward uncovering the role of protein dynamics in function. I will share how we have investigated dynamics involved in protein molecular recognition and catalysis.

3:20 - 3:50 pm | Sean Garrett-Roe, University of Pittsburgh, USA

2D-IR Spectroscopy of Ionic Liquids and Composite Materials

2D-IR spectroscopy of CO2 and other vibrational chromophores reveals structure and dynamics in ionic liquids and ionic liquid-polymer composite materials. Encapsulation of ionic liquids in a gel changes the rate of intramolecular vibrational energy relaxation. A matrix-shell-core model of how the gel affects the CO2 is presented.  

3:50 - 4:05 pm | Break

4:05 - 4:35 pm | Andrei Tokmakoff, University of Chicago, USA

Molecular Recognition and Binding Dynamics in DNA Hybridization

Time-resolved infrared spectroscopy following temperature-jump induced dissociation of duplex oligonucleotides is used to understand the mechanism of DNA hybridization.

4:35 - 5:05 pm | Tianquan Lian, Emory University, USA

In situ SFG Spectroscopic Probe of Molecular Catalysts at Electrochemical Interfaces

Attaching molecular catalysts onto semiconductor or metal electrodes is one of the most promising approaches for designing of (photo-)electrodes for CO2 reduction. We use in situ vibrational sum frequency generation spectroscopy to probe the structure, dynamics and reaction mechanisms of these catalysts at the electrode/liquid interface.

5:05 - 5:25 pm | Ariba Javed, University of Michigan, USA

Phase-Modulated Rapid-Scanning Fluorescence-Detected Two-Dimensional Electronic Spectroscopy

We present a continuous-scanning approach to fluorescence-detected two-dimensional electronic spectroscopy (FD-2DES) that combines acousto-optic phase-modulation with digital lock-in detection. The method allows retrieval of the complex linear and non-linear signals of interest simultaneously, tracking the time delays interferometrically and correcting for spectral phase distortions and enabling accurate phasing of the data.

5:45 pm | LUMOS Lab Tour in the Gather space (go through “Lab Tours” door)