2014/05/26 by Hiroki Fujiwara, Fujiwara, Hiroki
Engineering · Physics and Astronomy · #Advanced Chemical Physics Studies #Chemical Physics (physics.chem-ph) #FOS: Physical sciences #Materials Science (cond-mat.mtrl-sci) #Molecular Junctions and Nanostructures #Optics (physics.optics) #Spectroscopy and Quantum Chemical Studies
paper · pdf · doi:10.48550/arxiv.1405.6533
openalex publication_date 2014/05/26 · openalex created_date 2016/06/24 · openalex updated_date 2026/07/28
The picosecond thermal response of a normal octadecanethiol self-assembled monolayer on a gold surface was studied using pump-probe, broadband-infrared, background-suppressed and vibrational sum frequency generation spectroscopy. The orientation fluctuations in response to flash heating were characterized from the intensity kinetics of the terminal methyl C-H stretching vibrations. An intensity decrease (5.7 +/- 1.3 ps) in the asymmetric modes indicated that stochastic processes of molecular conformations developed during multiple light-matter interactions. Including torsional diffusion into the rotation term of second order electrosusceptibility explained the experimental surface temperature increment two order-of-magnitudes smaller than the activation energy of the dihedral angles (~15 K).