Highly Efficient Thermal and Light-Induced Spin-State Switching of an Fe(II) Complex in Direct Contact with a Solid Surface.
Spin crossover (SCO) complexes possess a bistable spin state that reacts sensitively to changes in temperature or excitation with light. These effects have been well investigated in solids and solutions, while technological applications require the immobilization and contacting of the molecules at surfaces, which often results in the suppression of the SCO. We report on the thermal and light-induced SCO of [Fe(bpz)2phen] molecules in direct contact with a highly oriented pyrolytic graphite surface. We are able to switch on the magnetic moment of the molecules by illumination with green light at T = 6 K, and off by increasing the temperature to 65 K. The light-induced switching process is highly efficient leading to a complete spin conversion from the low-spin to the high-spin state within a submonolayer of molecules. [Fe(bpz)2phen] complexes immobilized on weakly interacting graphite substrates are thus promising candidates to realize the vision of an optically controlled molecular logic unit for spintronic devices.
Institut für Experimentalphysik, Freie Universität Berlin , Arnimallee 14, 14195 Berlin, Germany.
Matthias
M
Bernien
Institut für Anorganische Chemie, Christian-Albrechts-Universität zu Kiel , Max-Eyth-Straße 2, 24098 Kiel, Germany.
Holger
H
Naggert
Institut für Experimentalphysik, Freie Universität Berlin , Arnimallee 14, 14195 Berlin, Germany.
Lucas M
LM
Arruda
Institut für Experimentalphysik, Freie Universität Berlin , Arnimallee 14, 14195 Berlin, Germany.
Lalminthang
L
Kipgen
Institut für Experimentalphysik, Freie Universität Berlin , Arnimallee 14, 14195 Berlin, Germany.
Fabian
F
Nickel
Institut für Experimentalphysik, Freie Universität Berlin , Arnimallee 14, 14195 Berlin, Germany.
Jorge
J
Miguel
Institut für Experimentalphysik, Freie Universität Berlin , Arnimallee 14, 14195 Berlin, Germany.
Christian F
CF
Hermanns
Institut für Experimentalphysik, Freie Universität Berlin , Arnimallee 14, 14195 Berlin, Germany.
Alex
A
Krüger
Institut für Experimentalphysik, Freie Universität Berlin , Arnimallee 14, 14195 Berlin, Germany.
Dennis
D
Krüger
Helmholtz-Zentrum Berlin für Materialien und Energie , Albert-Einstein-Straße 15, 12489 Berlin, Germany.
Enrico
E
Schierle
Helmholtz-Zentrum Berlin für Materialien und Energie , Albert-Einstein-Straße 15, 12489 Berlin, Germany.
Eugen
E
Weschke
Institut für Anorganische Chemie, Christian-Albrechts-Universität zu Kiel , Max-Eyth-Straße 2, 24098 Kiel, Germany.
Felix
F
Tuczek
Institut für Experimentalphysik, Freie Universität Berlin , Arnimallee 14, 14195 Berlin, Germany.
Wolfgang
W
Kuch
X-ray absorption spectroscopy; light-induced excited spin-state trapping; molecular switches; spin crossover; surfaces