title: Structure and Bonding in Nickel-Thiolate-Iodine Charge-Transfer Complexes.
abstract: The dinuclear nickel complexes [Ni2L(μ-O2CR)](ClO4) [R=Me (4), R=OMe (6)], where L2-is a 24-membered macrocyclic N6S2ligand, react readily with excess I2in MeCN solution at 4 °C to form stable mono-(I2) and bis-(I2) charge-transfer (CT) adducts of the type [Ni2L(μ-O2CR)(I2)n]+(n=1 or 2) containing linear RS-I-I linkages. Three new CT compounds, namely, [Ni2L(OAc)(I2)](I2)(I3) (5), [Ni2L(O2COMe)(I2)](I5)⋅MeCN (7⋅MeCN), and [Ni2L(O2COMe)(I2)2](I5)⋅MeCN (8⋅MeCN) as well as the triiodide salt [Ni2L(OAc)](I3) (9) were synthesized and fully characterized. A common feature of the CT adducts is a polyiodide matrix, which surrounds the individual complex molecules, stabilized by secondary I⋅⋅⋅I interactions with the CT linkages. The scatter in both the RS-I (2.6 to 3.0 Å) and the I-I bond lengths (2.7 to 3.0 Å) is indicative of both a variable strength of the RS-→I2bond and a varying degree of charge transfer. An analysis of the structural parameters was undertaken accompanied by DFT calculations to quantify the donating ability of the bridging thiolate functions and to shed more light on the bonding in this rare sort of charge-transfer complexes. The stability of the CT complexes and the results of preliminary transport measurements are also reported.
authors: Institut für Anorganische Chemie, Universität Leipzig, 04103, Leipzig, Germany.
authors: Norman
authors: N
authors: Beyer
authors: Institut für Anorganische Chemie, Universität Leipzig, 04103, Leipzig, Germany.
authors: Gunther
authors: G
authors: Steinfeld
authors: Institut für Anorganische Chemie, Universität Leipzig, 04103, Leipzig, Germany.
authors: Vasile
authors: V
authors: Lozan
authors: Leibniz-Institut für Oberflächenmodifizierung e.V., Chemische Abteilung, 04318, Leipzig, Germany.
authors: Sergej
authors: S
authors: Naumov
authors: Leibniz-Institut für Oberflächenmodifizierung e.V., Chemische Abteilung, 04318, Leipzig, Germany.
authors: Roman
authors: R
authors: Flyunt
authors: Leibniz-Institut für Oberflächenmodifizierung e.V., Chemische Abteilung, 04318, Leipzig, Germany.
authors: Bernd
authors: B
authors: Abel
authors: Institut für Anorganische Chemie, Universität Leipzig, 04103, Leipzig, Germany.
authors: Berthold
authors: B
authors: Kersting
keywords: charge transfer; crystal structures; density functional calculations; iodine; nickel thiophenolate complexes