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arXiv · 1604.00977

Molecular Dynamics at Electrical- and Optical-Driven Phase Transitions Time-Resolved Infrared Studies Using Fourier-Transform Spectrometers

Tobias Peterseim·Martin Dressel
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Abstract

The time-dependent optical properties of molecular systems are investigated by step-scan Fourier-transform spectroscopy in order to explore the dynamics at phase transitions and molecular orientation in the milli- and microsecond range. The electrical switching of liquid crystals traced by vibrational spectroscopy reveals a rotation of the molecules with a relaxation time of 2 ms. The photo-induced neutral-ionic transition in TTF-CA takes place by a suppression of the dimerization in the ionic phase and creation of neutral domains. The time-dependent infrared spectra depend on temperature and laser pulse intensity; the relaxation of the spectra follows a stretched-exponential decay with relaxation times in the microsecond range strongly dependent on temperature and laser intensity. We present all details of the experimental setups and thoroughly discuss the technical challenges.

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Tobias Peterseim, Martin Dressel. 2016-04-04. Molecular Dynamics at Electrical- and Optical-Driven Phase Transitions Time-Resolved Infrared Studies Using Fourier-Transform Spectrometers. https://doi.org/10.1007/s10762-016-0294-5

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