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Direct structural evidence of the presence and location of the attached proton in the protonated form of rare earth bis(porphyrinato) double-decker complexes is obtained from an X-ray diffraction study of single crystals for a series of protonated forms of bis(tetraphenylporphyrinato) complexes [M(III)(tpp)(tppH)] (M = Tb, Y, Sm, Nd, and La). When CHCl3 is used as a solvent for crystallization of the complexes, their nondisordered molecular structures are obtained and the attached proton is identified on one of the eight nitrogen atoms. Use of other solvents affords another type of crystal, in which the position of the proton is disordered and thus the molecular structure is averaged. La complex also affords the disordered average structure even when CHCl3 is used for crystallization. A variable-temperature diffraction study for the Tb complex reveals that the dynamics of the proton in the nondisordered crystal is restricted.

The synthesis, characterization, and X-ray structure of the first example of an air-stable silver(III) complex of an N-confused tetraphenylporphyrin (5,10,15,20-tetraphenyl-2-aza-21-carbaporphyrin argentate(III) or Ag(III)NCTPP, 7) is reported. Crystals of Ag(III)NCTPP·CH2Cl2 belong to the monoclinic space group P21/c (No. 14), with a = 9.038(4) A, b = 15.097(3) A, c = 25.578(8) A, β = 91.32(3)°, and Z = 4. The lengths (A) of the three silver−nitrogen and one silver−carbon bonds are inequivalent [Ag−N(1), 2.06(2); Ag−N(2), 2.08(2); Ag−N(3), 2.03(2); and Ag−C(17), 2.04(2)], reflecting the asymmetric structure of the NCTPP ligand. The very small distortion from a square planar geometry is shown in N−Ag−N and N−Ag−C angles (degrees): N(1)−Ag−N(2), 89.7(8); N(1)−Ag−N(3), 179(1); N(1)−Ag−C(17), 90.3(9); N(2)−Ag−N(3), 89.6(9); N(2)−Ag−C(17), 179(1); and N(3)−Ag−C(17), 90.9(1). The diamagnetic nature of Ag(III)NCTPP was confirmed by 1H and 13C NMR and magnetic susceptibility measurements. Electrochemical and sp...

A multistep synthesis was achieved to obtain 3,8-bis(4-mercaptophenyl)-1,10-phenanthroline, which has two free thiol end groups with a molecular length of 1.89 nm, and its ruthenium(II) complex. Five single-crystal structures and UV-vis spectra of related intermediates in methanol and the solid state were studied in order to obtain additional information on the molecules as well as on the supramolecular interactions in the structures. Thermal and electrochemical properties of related Ru(II) complexes were also involved. 3,8-Bis(4-mercaptophenyl)-1,10-phenanthroline and one of its ruthenium(II) complexes were then treated with gold nanoparticles (Au-NPs) via in situ thiol-to-thiol ligand exchange in the presence of two facing Au electrodes with a 1 x 1 microm(2) gap. Stable molecular junctions composed of self-assembled films were produced as revealed by an obvious increase of the conductivity between the Au electrodes, wherein dithiols-bridged Au-NPs were attached to the electrodes by means of Au-S-bonded contacts. Temperature-dependent current-voltage (I-V) measurements for the junctions were performed in the temperature range of 7-300 K, and classical Arrhenius plots and their linear fits were obtained to determine the average activation energies (DeltaE) of these devices. It is found that when the Ru(II) ion is introduced, the conductivity of the nanodevice is increased and the energy barrier is lowered under the same experimental conditions.

An inner-coordinated Pd complex and inner- and outer-N coordinated, double-decker Pd complexes of N-confused tetratolylporphyrin have been synthesized, and their structures were elucidated by X-ray single-crystal analyses.