An excitation-wavelength-dependent luminescence behavior of a bipyridinium derivative, together with its luminescence switching between single- and dual-emissions upon reversible solid state structural transformation, has been presented.

Let e be an edge of a G connecting the vertices u and v. Define two sets N1 (e | G) and N2(e |G) as N1(e | G)= {xV(G) d(x,u) d(x,v)} and N2(e | G)= {xV(G) d(x,v) d(x,u) }.The number of elements of N1(e | G) and N2(e | G) are denoted by n1(e | G) and n2(e | G) , respectively. The Szeged index of the graph G is defined as Sz(G) ( ) ( ) 1 2 n e G n e G e E    . In this paper we compute th...

A series of pyridinium and bipyridinium salts were prepared their catalytic properties evaluated in the aza-Diels-Alder reaction between imines Danishefsky diene. Depending on substituents pyridinium/bipyridinium rings nature counterion, two mechanisms activation demonstrated. In case non-substituted rings, substrate is activated through charge transfer involving aryl ring C-side imine. When ha...

The title compound, (C(10)H(10)N(2))[Sb(2)(C(7)H(2)NO(5))(2)(OH)(2)(H(2)O)(2)]·2H(2)O, consists of a binuclear anion, a diprotonated 4,4'-bipyridinium cation and two uncoordinated water mol-ecules. Each Sb(III) atom is six-coordinated by one chelating 4-oxidopyridine-2,6-dicarboxyl-ate ligand, one water mol-ecule, one OH group and one bridging O atom from a neighboring carboxyl-ate group in a d...

In the title compound, C(12)H(14)N(2) (2+)·2Cl(-), the 4,4'-dimethyl-2,2'-bipyridinium cation is essentially planar (r.m.s. deviation for all non-H atoms = 0.004 Å) and is located on a crystallographic inversion centre. The cations and chloride anions lie in planes parallel to (111) and are connected by N-H⋯Cl and C-H⋯Cl hydrogen bonds.

A PV was synthesized by polymerization of N,N0-bis(d-aminopropyl)-4,40-bipyridinium bromide hydrobromide (APD) and isophthaloyl chloride (ISP). The PV was completely soluble in water as well as in organic solvents. The spectroelectrochemical and EC properties of the resulting ionic self-assembled multilayers of PV/poly(2-acrylamido-2-methylpropanesulfonic acid) (PAMPs) were examined by cyclic v...

So-called bottom-up fabrication methods aim to assemble and integrate molecular components exhibiting specific functions into electronic devices that are orders of magnitude smaller than can be fabricated by lithographic techniques. Fundamental to the success of the bottom-up approach is the ability to control electron transport across molecular components. Organic molecules containing redox ce...

The title compound, (C(10)H(10)N(2))(2)[SiW(12)O(40)]·C(10)H(8)N(2)·6H(2)O or (4,4'-bipyH(2))(2)[SiW(12)O(40)].(4,4'-bipy)·6H(2)O (4,4'-bipy is 4,4'-bipyridine), was prepared under hydro-thermal conditions. The asymmetric unit contains a discrete Keggin-type [SiW(12)O(40)](4-) anion (located on a twofold axis), one 4,4'-bipy (located on a twofold axis), two (4,4'-bipyH(2))(2+) cations and six u...