TY  - JOUR
A1  - Schulze, Michael
A1  - Utecht, Manuel Martin
A1  - Hebert, Andreas
A1  - Rück-Braun, Karola
A1  - Saalfrank, Peter
A1  - Tegeder, Petra
T1  - Reversible Photoswitching of the Interfacial Nonlinear Optical Response
JF  - The journal of physical chemistry letters
N2  - Incorporating photochromic molecules into organic/inorganic hybrid materials may lead to photoresponsive systems. In such systems, the second-order nonlinear properties can be controlled via external stimulation with light at an appropriate wavelength. By creating photochromic molecular switches containing self-assembled monolayers on Si(111), we can demonstrate efficient reversible switching, which is accompanied by a pronounced modulation of the nonlinear optical (NLO) response of the system. The concept of utilizing functionalized photoswitchable Si surfaces could be a way for the generation of two-dimensional NLO switching materials, which are promising for applications in photonic and optoelectronic devices.
Y1  - 2015
U6  - https://doi.org/10.1021/jz502477m
SN  - 1948-7185
VL  - 6
IS  - 3
SP  - 505
EP  - 509
PB  - American Chemical Society
CY  - Washington
ER  - 
TY  - JOUR
A1  - Wirth, Jonas
A1  - Hatter, Nino
A1  - Drost, Robert
A1  - Umbach, Tobias R.
A1  - Barja, Sara
A1  - Zastrow, Matthias
A1  - Rück-Braun, Karola
A1  - Pascual, Jose Ignacio
A1  - Saalfrank, Peter
A1  - Franke, Katharina J.
T1  - Diarylethene Molecules on a Ag(111) Surface: Stability and Electron-Induced Switching
JF  - The journal of physical chemistry : C, Nanomaterials and interfaces
N2  - Diarylethene derivatives are photochromic molecular switches, undergoing a ring-opening/-closing reaction by illumination with light. The symmetry of the closed form is determined by the WoodWard Hoffinann rules according to which the reaction proceeds by corirotatory rotation -in that case. Here, we show by a cOrnbined approach of scanning tunneling microscopy (STM) and density functional theory (DFT) calculations that the Open isomer of 4,4'-(4,4'-(perfluorocydopent-1-ene-1,2-diyl)bis(5-methyl-thiophent-4,2,4-dipyridine) (PDTE) retains its open form upon adsorption on a Ag(111) surface. It caribe switched into a closed form, which we identify as the digrotatOly cydization product, by controlled manipulation 'With the STM tip, Evidence of an electric-field dependent switching-process 'is interpreted on the basis of a Simple electroStatic Model, which suggests that the reaction proceedS via an "upright" intermediate state. This pathway thus strongly differs from the switching reaction in solution.
Y1  - 2015
U6  - https://doi.org/10.1021/jp5122036
SN  - 1932-7447
VL  - 119
IS  - 9
SP  - 4874
EP  - 4883
PB  - American Chemical Society
CY  - Washington
ER  -