Charge-Separation-Type Ionic Crystals with Mixed AuI4CoIII2 and AuI4NiIICoIII Hexanuclear Complexes
journal contributionposted on 2020-05-07, 13:22 authored by Rycce S. Pratikha, Tatsuhiro Kojima, Naoto Kuwamura, Nobuto Yoshinari, Takumi Konno
Treatment of a digold(I) metalloligand, [AuI2(dppe)(d-Hpen)2] (H2LAu; d-H2pen = d-penicillamine, dppe = 1,2-bis(diphenylphosphino)ethane), with a 1:1 mixture of Co(OAc)2 and Ni(OAc)2 under aerobic conditions resulted in the formation of three types of hexanuclear complexes: [CoIII2(LAu)2]2+, [NiIICoIII(LAu)2]+, and [NiII2(LAu)2]. The addition of NaNO3, M1NO3 (M1 = K, Rb, Cs), and M2(NO3)2 (M2 = Ca, Sr, Ba) to the reaction mixture led to co-crystallization of [CoIII2(LAu)2]2+ and [NiIICoIII(LAu)2]+ as a solid solution to form the charge-separation (CS)-type ionic crystals 1Na, 1M1, and 1M2, respectively, while [NiII2(LAu)2] independently crystallized as a single species (2). In 1Na, [CoIII2(LAu)2]2+ and [NiIICoIII(LAu)2]+ cations assemble in a 1:2 ratio to form a cationic supramolecular octahedron accommodating 4 H3O+ ions, while 10 nitrate ions are packed in each hydrophilic tetrahedral interstice of the crystal to form an anionic adamantane cluster. The overall structures of 1M1 and 1M2 are very similar to that of 1Na, having a CS-type structure composed of cationic supramolecular octahedra with a +12 charge and anionic inorganic clusters with a −10 charge. However, 1M1 contains M1 ions in place of the H3O+ ions in 1Na, and furthermore, a novel rhombic dodecahedron cluster composed of 14 nitrate ions, which encapsulates two M2 ions, is formed in each hydrophilic tetrahedral interstice in 1M2.
4 Ni II Co III Hexanuclear Complexes Treatment4 H 3 O10 nitrate ionsM 2 ionstetrahedral intersticenovel rhombic dodecahedron clusterd-H 2 penNi II Co III4 Co III 214 nitrate ionsH 2 LCScrystals 1 NaM 2M 1H 3 ONi II 21 NaM 1 ions1 M 2cationic supramolecular octahedra1 M 1cationic supramolecular octahedronCo III 2