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Seeing with the nano-eye: imaging structure, coupling and dynamics on the molecular scale

Kolloquium der Abteilung 7

Intra- and intermolecular interactions determine chemical reaction, charge transfer, and catalytic activity. Vibrational infrared spectroscopy can provide information about structure, coupling and dynamics underlying these functions of molecular systems. I will discuss the combination of optical nano-probe imaging with ultra-broadband synchrotron and ultrafast and shaped IR pulses for few-nanometer spatially resolved vibrational nano-scopy. Probing selected vibrational resonances as intrinsic molecular labels provides exquisitely sensitive insight into the local chemical environment. Examples include vibrational solvatochromism studying nanoscale phase separation, a new form of optical nano-crystallography based on the anisotropy of the vibrational molecular response, vibrational exciton formation as a molecular ruler to access molecular order and coupling, or probing of static and dynamics contributions to ultrafast vibrational dephasing. Further in the extension to the strong coupling regime we envision new forms of molecular vibrational spectroscopy and control of vibrational coherence for new avenues from quantum photochemistry to nano-cavity opto-mechanics with single vibrational quanta.