title: Spin-crossover complex on Au(111): structural and electronic differences between mono- and multilayers.
abstract: Submono-, mono- and multilayers of the Fe(II) spin-crossover (SCO) complex [Fe(bpz)2 (phen)] (bpz=dihydrobis(pyrazolyl)borate, phen=1,10-phenanthroline) have beenprepared by vacuum deposition on Au(111) substrates and investigated with near edge X-ray absorption fine structure (NEXAFS) spectroscopy and scanning tunneling microscopy (STM). As evidenced by NEXAFS, molecules of the second layer exhibit a thermal spin crossover transition, although with a more gradual characteristics than in the bulk. For mono- and submonolayers of [Fe(bpz)2 (phen)] deposited on Au(111) substrates at room temperature both NEXAFS and STM indicate a dissociation of [Fe(bpz)2 (phen)] on Au(111) into four-coordinate complexes, [Fe(bpz)2 ], and phen molecules. Keeping the gold substrate at elevated temperatures ordered monolayers of intact molecules of [Fe(bpz)2 (phen)] are formed which can be spin-switched by electron-induced excited spin-state trapping (ELIESST).
authors.affiliation: Institut für Experimentelle und Angewandte Physik, Christian-Albrechts-Universität zu Kiel, 24098 Kiel (Germany).
authors.forename: Thiruvancheril G
authors.initials: TG
authors.lastname: Gopakumar
authors.forename: Matthias
authors.initials: M
authors.lastname: Bernien
authors.forename: Holger
authors.initials: H
authors.lastname: Naggert
authors.forename: Francesca
authors.initials: F
authors.lastname: Matino
authors.forename: Christian F
authors.initials: CF
authors.lastname: Hermanns
authors.forename: Alexander
authors.initials: A
authors.lastname: Bannwarth
authors.forename: Svenja
authors.initials: S
authors.lastname: Mühlenberend
authors.forename: Alex
authors.initials: A
authors.lastname: Krüger
authors.forename: Dennis
authors.initials: D
authors.lastname: Krüger
authors.forename: Fabian
authors.initials: F
authors.lastname: Nickel
authors.forename: Waldemar
authors.initials: W
authors.lastname: Walter
authors.forename: Richard
authors.initials: R
authors.lastname: Berndt
authors.forename: Wolfgang
authors.initials: W
authors.lastname: Kuch
authors.forename: Felix
authors.initials: F
authors.lastname: Tuczek
keywords: X-ray absorption spectroscopy; gold; iron; scanning tunnel microscopy; spin crossover; spintronics