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  - 
TY  - JOUR
A1  - Heinrich, Benjamin W.
A1  - Ehlert, Christopher
A1  - Hatter, Nino
A1  - Braun, Lukas
A1  - Lotze, Christian
A1  - Saalfrank, Peter
A1  - Franke, Katharina J.
T1  - Control of oxidation and spin state in a single-molecule junction
JF  - ACS nano
N2  - The oxidation and spin state of a metal-organic molecule determine its chemical reactivity and magnetic properties. Here, we demonstrate the reversible control of the oxidation and spin state in a single Fe porphyrin molecule in the force field of the tip of a scanning electron tunneling microscope. Within the regimes of half-integer and integer spin state, we can further track the evolution of the magnetocrystalline anisotropy. Our experimental results are corroborated by density functional theory and wave function theory. This combined analysis allows us to draw a complete picture of the molecular states over a large range of intramolecular deformations.
KW  - porphyrin
KW  - oxidation state
KW  - spin state
KW  - scanning tunneling microscopy
KW  - scanning tunneling spectroscopy
KW  - density functional theory
Y1  - 2018
U6  - https://doi.org/10.1021/acsnano.8b00312
SN  - 1936-0851
SN  - 1936-086X
VL  - 12
IS  - 4
SP  - 3172
EP  - 3177
PB  - American Chemical Society
CY  - Washington
ER  -