title: Linear coordination fullerene C60 polymer [{Ni(Me3P)2}(μ-η(2),η(2)-C60)]∞ bridged by zerovalent nickel atoms.
abstract: Coordination nickel-bridged fullerene polymer [{Ni(Me3P)2}(μ-η(2),η(2)-C60)]∞ (1) has been obtained via reduction of a Ni(II)(Me3P)2Cl2 and C60 mixture. Each nickel atom is linked in the polymer with two fullerene units by η(2)-type Ni-C(C60) bonds of 2.087(8)-2.149(8) Å length. Nickel atoms are coordinated to the 6-6 bonds of C60 as well as two trimethylphosphine ligands to form a four-coordinated environment around the metal centers. Fullerene cages approach very close to each other in the polymer with a 9.693(3) Å interfullerene center-to-center distance, and two short interfullerene C-C contacts of 2.923(7) Å length are formed. Polymer chains are densely packed in a crystal with interfullerene center-to-center distances between fullerenes from neighboring polymer chains of 9.933(3) Å and multiple interfullerene C···C contacts. As a result, three-dimensional dense fullerene packing is formed in 1. According to optical and electron paramagnetic resonance spectra, fullerenes are neutral in 1 and nickel atoms have a zerovalent state with a diamagnetic d(10) electron configuration. The density functional theory calculations prove the diamagnetic state of the polymer with a singlet-triplet gap wider than 1.37 eV.
authors.affiliation: Institute of Problems of Chemical Physics and §Institute of Solid State Physics, Russian Academy of Sciences , Chernogolovka, Moscow 142432, Russia.
authors.forename: Dmitri V
authors.initials: DV
authors.lastname: Konarev
authors.forename: Salavat S
authors.initials: SS
authors.lastname: Khasanov
authors.forename: Yoshiaki
authors.initials: Y
authors.lastname: Nakano
authors.forename: Akihiro
authors.initials: A
authors.lastname: Otsuka
authors.forename: Hideki
authors.initials: H
authors.lastname: Yamochi
authors.forename: Gunzi
authors.initials: G
authors.lastname: Saito
authors.forename: Rimma N
authors.initials: RN
authors.lastname: Lyubovskaya