Communication pubs.acs.org/JACS
Multiple-Hydrogen-Bond Approach to Uncommon Pd(III) Oxidation State: A Pd−Br Chain with High Conductivity and Thermal Stability Mohammad Rasel Mian,† Hiroaki Iguchi,*,† Shinya Takaishi,† Hideaki Murasugi,† Tatsuya Miyamoto,‡ Hiroshi Okamoto,‡ Hisaaki Tanaka,§ Shin-ichi Kuroda,§ Brian K. Breedlove,† and Masahiro Yamashita*,†,∥,⊥ †
Department of Chemistry, Graduate School of Science, Tohoku University, 6-3 Aza-Aoba, Aramaki, Sendai 980-8578, Japan Department of Advanced Materials Science, Graduate School of Frontier Sciences, The University of Tokyo, Kashiwa 277-8561, Japan § Department of Applied Physics, Graduate School of Engineering, Nagoya University, Chikusa, Nagoya 464-8603, Japan ∥ Advanced Institute for Materials Research, Tohoku University, 2-1-1 Katahira, Aoba-ku, Sendai 980-8577, Japan ⊥ School of Materials Science and Engineering, Nankai University, Tianjin 300350, China ‡
S Supporting Information *
the functionality and durability of Pd(III) chain complexes. The Pd(III)Br chains have been prepared in a low temperature phase, so-called averaged valence (AV) state (−PdIII−Br−PdIII−Br−) by introducing a counteranion (Y) with alkyl chains. Singlecrystalline Pd(III)Br chains, [Pd(en)2Br](Y)2·H2O (en = ethylenediamine, Y = dipentylsulfosuccinate (1),6 diheptylsulfomalonate (2)7), have been reported to be in an AV state below 206 K for 1 and below 310 K for 2. Above the transition temperature (Tc ), the Pd(III) ions disproportionate to alternating array of Pd(II) and Pd(IV) ions, which is a mixed valence (MV) state (···PdII···Br−PdIV−Br···PdII···Br−PdIV− Br···). The Pd(III) AV state which is stable at any temperature (no phase transition to MV state) has never been realized. Furthermore, thin crystals of 1 and 2 are too fragile for optical experiment, and their low crystallinity causes a low σ (
