title: Iodobismuthates with N-alkyl- or N,N'-dialkyl-4,4'-bipyridinium: syntheses, structures and dielectric properties.
abstract: The solvothermal reactions of BiI(3), KI, I(2), 4,4'-bipyridine (4,4'-bipy), and a small amount of water in alcohol and acetonitrile produced four bipyridinium iodobismuthates {[MQ](3)[Bi(2)I(6)(μ-I)(3)][Bi(2)I(6)(μ-I)(2)(MQ)(2)](3)} (1, MQ(+) = N-methyl-4,4'-bipyridinium), {[EQ](3)[Bi(2)I(6)(μ-I)(3)][Bi(2)I(6)(μ-I)(2)(EQ)(2)](3)} (2, EQ(+) = N-ethyl-4,4'-bipyridinium), [MV][BiI(5)] (Eur. J. Inorg. Chem., 2010, 5326) (3, MV(2+) = N,N'-dimethyl-4,4'-bipyridinium), and [EV](2)[Bi(4)I(10)(μ-I)(4)(μ(3)-I)(2)] (4, EV(2+) = N,N'-diethyl-4,4'-bipyridinium). In these reactions, 4,4'-bipy was partly or completely alkylated by alkyl groups generated from the cleavage of C-O bond of alcohols, forming the N-alkyl-4,4'-bipyridinium cation (Q(+)) and the N,N'-dialkyl-4,4'-bipyridinium dication (V(2+)), respectively. Compounds 1-4 were characterized by elemental analysis, IR, (1)H NMR and single-crystal X-ray diffraction analysis. The optical, electrical conductive and dielectric properties of these compounds were investigated. The dielectric constants of the Q(+)-based compounds were larger than the values of the V(2+)-based ones, which showed that the weak electrostatic interactions in the structures may benefit the polarizability of molecules, thereby resulting in a larger dielectric response of the structures under an external electric field, while the strong electrostatic interactions between the positive and negative charge units would lead to a low dielectric constant (low-k) behavior of these compounds.
authors.affiliation: College of Chemistry, Chemical Engineering and Materials Science, Soochow University, Suzhou, Jiangsu, P R China.
authors.forename: Yang
authors.initials: Y
authors.lastname: Chen
authors.forename: Zhou
authors.initials: Z
authors.lastname: Yang
authors.forename: Xin-Yi
authors.initials: XY
authors.lastname: Wu
authors.forename: Chun-Yan
authors.initials: CY
authors.lastname: Ni
authors.forename: Zhi-Gang
authors.initials: ZG
authors.lastname: Ren
authors.forename: Hui-Fang
authors.initials: HF
authors.lastname: Wang
authors.forename: Jian-Ping
authors.initials: JP
authors.lastname: Lang
mesh_terms: D000097:Acetonitriles / Q000737:chemistry; D000438:Alcohols / Q000737:chemistry; D001729:Bismuth / Q000737:chemistry*; D018360:Crystallography, X-Ray; D004563:Electrochemistry; D007454:Iodides / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy; D015394:Molecular Structure; D011725:Pyridines / Q000737:chemistry*; D014867:Water / Q000737:chemistry
chemical_list: D000097:Acetonitriles; D000438:Alcohols; D007454:Iodides; D011725:Pyridines; D014867:Water; C048121:bismuth iodide; D001729:Bismuth; C034306:4,4'-bipyridyl; C032159:acetonitrile