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  - 
TY  - JOUR
A1  - Maier, Stefan K.
A1  - Poluektov, Georgiy
A1  - Jester, Stefan-S.
A1  - Möller, Heiko Michael
A1  - Hoeger, Sigurd
T1  - Fast Oxidative Cyclooligomerization towards Low- and High-Symmetry Thiophene Macrocycles
JF  - Chemistry - a European journal
N2  - Macrocycles with quaterthiophene subunits were obtained by cyclooligomerization by direct oxidative coupling of unsubstituted dithiophene moieties. The rings were closed with high selectivity by an α,β′-connection of the thiophenes as proven by NMR spectroscopy. The reaction of the precursor with terthiophene moieties yielded the symmetric α,α′-linked macrocycle in low yield together with various differently connected isomers. Blocking of the β-position of the half-rings yielded selectively the α,α′-linked macrocycle. Selected cyclothiophenes were investigated by scanning tunneling microscopy, which displayed the formation of highly ordered 2D crystalline monolayers.
KW  - cyclooligomers
KW  - scanning tunneling microscopy
KW  - self-assembled monolayers
KW  - shape-persistent macrocycles
KW  - thiophenes
Y1  - 2016
U6  - https://doi.org/10.1002/chem.201503211
SN  - 0947-6539
SN  - 1521-3765
VL  - 22
SP  - 1379
EP  - 1384
PB  - Wiley-VCH
CY  - Weinheim
ER  -