Iron(II) spin-crossover complexes in ultrathin films: electronic structure and spin-state switching by visible and vacuum-UV light

E Ludwig; H Naggert; M Kalläne; S Rohlf; E Kröger; A Bannwarth; A Quer; K Rossnagel; L Kipp; F Tuczek

doi:10.1002/anie.201307968

Iron(II) spin-crossover complexes in ultrathin films: electronic structure and spin-state switching by visible and vacuum-UV light

Angew Chem Int Ed Engl. 2014 Mar 10;53(11):3019-23. doi: 10.1002/anie.201307968. Epub 2014 Feb 12.

Authors

E Ludwig¹, H Naggert, M Kalläne, S Rohlf, E Kröger, A Bannwarth, A Quer, K Rossnagel, L Kipp, F Tuczek

Affiliation

¹ Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel, 24098 Kiel (Germany) www.ieap.uni-kiel.de/surface/ag-kipp.

PMID: 24519743
DOI: 10.1002/anie.201307968

Abstract

The electronic structure of the iron(II) spin crossover complex [Fe(H2bpz)2(phen)] deposited as an ultrathin film on Au(111) is determined by means of UV-photoelectron spectroscopy (UPS) in the high-spin and in the low-spin state. This also allows monitoring the thermal as well as photoinduced spin transition in this system. Moreover, the complex is excited to the metastable high-spin state by irradiation with vacuum-UV light. Relaxation rates after photoexcitation are determined as a function of temperature. They exhibit a transition from thermally activated to tunneling behavior and are two orders of magnitude higher than in the bulk material.

Keywords: molecular switches; spin crossover; thin films; ultraviolet photoelectron spectroscopy.