title: Rational design of a room temperature molecular spin switch. The light-driven coordination induced spin state switch (LD-CISSS) approach.
abstract: Extensive use of quantum chemical calculations has been made to rationally design a molecule whose spin state can be switched reversibly using light of two different wavelengths at room temperature in solution. Spin change is induced by changing the coordination number of a nickel complex. The coordination number in turn is switched using a photochromic ligand that binds in one configuration and dissociates in the other. We demonstrate that successful design relies on a precise geometry fit and delicate electronic tuning. Our designer complex exhibits an extremely high long-term switching stability (more than 20 000 cycles) and a high switching efficiency. The high-spin state is extraordinarily stable with a half-life of 400 days at room temperature. Switching between the dia- and paramagnetic state is achieved with visible light (500 and 430 nm). The compound can also be used as a molecular logic gate with light and pH as input and the magnetic state as non-destructive read-out.
authors.affiliation: Otto-Diels-Institut für Organische Chemie, Christian-Albrechts-Universität, Otto-Hahn-Platz 4, D-24098 Kiel, Germany. rherges@oc.uni-kiel.de.
authors.forename: M
authors.initials: M
authors.lastname: Dommaschk
authors.forename: C
authors.initials: C
authors.lastname: Schütt
authors.forename: S
authors.initials: S
authors.lastname: Venkataramani
authors.forename: U
authors.initials: U
authors.lastname: Jana
authors.forename: C
authors.initials: C
authors.lastname: Näther
authors.forename: F D
authors.initials: FD
authors.lastname: Sönnichsen
authors.forename: R
authors.initials: R
authors.lastname: Herges