The organic mol-ecule of the title compound, C(16)H(12)N(6)O(2)·2H(2)O, lies across a crystallographic inversion centre. The dihedral angle between the pyrimidine and benzene rings is 80.78 (6)°. The two pyrimidine rings are parallel by virtue of the centre of symmetry. The pyrimidine and benzene rings form dihedral angles of 41.41 (7) and 40.26 (7)°, respectively, with the amide plane. The mol...

Cyclobis(paraquat-p-phenylene)s complexed with anionic surfactants exhibit liquid-crystalline states and form pseudorotaxanes with tetrathiafulvalene in the condensed states.

Helical periodic mesoporous 1,4-phenylene-silica nanorods with chiral crystalline walls were prepared using the self-assembly of a pair of enantiomers as templates.

Two three-dimensional catenanes have been successfully synthesized from a bis(m-phenylene)-32-crown-10-based cryptand and paraquat derivatives in reasonable yields.

Pi-pi stacking of hydrogen-bonded porphyrin and oligo(p-phenylene vinylene)s (OPVs) yields helical co-assemblies which exhibit energy transfer from OPV to porphyrin.

We study single-molecule oligo(phenylene ethynylene)dithiol junctions by means of inelastic electron tunneling spectroscopy (IETS). The molecule is contacted with gold nano-electrodes formed with the mechanically controllable break junction technique. We record the IETS spectrum of the molecule from direct current measurements, both as a function of time and electrode separation. We find that f...

Self-assembled monolayers (SAMs) of arylene-ethynylene oligomers that incorporate electron-accepting 9-fluorenone and 9-[(4-pyridyl)methylene]fluorene units in the backbone exhibit symmetrical current-voltage (I-V) characteristics, but rectifying junctions with current ratios of 20-80 at +/-1 V have been obtained by protonating these wire-like molecules and ionically coupling with anionic donors.

We have studied electron transport properties of unsubstituted oligo(phenylene ethynylene) (OPE) (1) and nitro-substituted OPE (2) covalently bound to two gold electrodes. The conductance values of single 1 and 2 are approximately 13 and approximately 6 nS, respectively. In addition to a decrease in the conductance, the presence of the nitro moiety leads to asymmetric I-V characteristics and a ...

Direct detection of pyrophosphate (PPi) in aqueous solution is demonstrated using a cationic poly(phenylene-ethynylene) with polyamine side chains. Pyrophosphate-induced polymer aggregation causes a significant spectroscopic change, which in turn allows quantification of dissolved PPi using ratiometric signals.

In the title compound, [AgBr(C(7)H(10)N(2))](n), adjacent Ag(I) atoms are bridged by bidentate CNCH(2)C(CH(3))(2)CH(2)NC ligands via the NC groups, forming [Ag{CNCH(2)C(CH(3))(2)CH(2)NC}](n) chains with the metal atom in a distorted tetrahedral coordination. The bromide counter-anions cross-link the Ag(I) atoms of the chains, forming a two-dimensional polymeric network {[Ag(I)(CNCH(2)C(CH(3))(2...