A. Haj Said

Structural and electronic properties of poly(meta/para phenylene)

We have recently synthesised a random poly(meta/para phenylene) (PMPP) by an electrochemical method from p-methoxytoluene and fractionated on three-chain length compounds. Moreover, these fractions can be deposited by vacuum sublimation on indium tin oxide (ITO) substrates. Various characterisation methods are allowed which facilitated the understanding of the structural, electronic and optical properties of the PMPPs and a tentative of their correlation to chain length was presented.

Submicron Particles of Metal–Organic Framework HKUST-1 with Negative Surface Charge and Their Electrophoretic Deposition on ITO

Negatively charged submicron-sized metal organic framework crystals (HKUST-1) were prepared using the 4-sulfobenzoic acid potassium salt as a crystal growth modulator. As shown by dynamic light scattering, average particle size was 730-370 nm depending on the sulfobenzoate content. Thin films of the obtained MOFs were successfully deposited on an indium tin oxide electrode using electrophoretic deposition. It was shown that the HKUST-1 crystals could act as seeds for larger crystals growth.

Theoretical investigation of oligomer structure and optoelectronic properties for [4-(methoxyphenyl)acetonitrile]n (n=1-5)

AbstractExperimental measurement on oligomeric 4-(methoxyphenyl)acetonitrile (OMPA) synthesized via an electrochemical method indicated that the average chain length for OMPA was around 5 units (5-MPA) [J Mol Struct 1031:186 (2013)], but did not provide enough information to completely characterize the chemical structure of the molecule. Nevertheless a possible structure was proposed on the basis of 13C NMR and the spin density hypothesis for radical polymerization. A more complete validation of the resultant structure is needed to show the extent to which the structure is consistent with a variety of measured properties. This is done here for the infrared (IR), ultraviolet–visible (UV–vis), and photoluminescence (PL) spectra of 5-MPA which are found to agree reasonably well with the experimentally measured spectra of OMPA. Electronic structure information regarding the highest-occupied molecular orbital (HOMO) and the lowest-unoccupied molecular orbital (LUMO) energies, ionization potentials and electron affinities, as well as optical properties (UV–vis, PL) is also provided. Graphical AbstractComparison of theoretical and experimental UV-visible absorption and photoluminescence spectra of oligomeric 4-(methoxyphenyl)acetonitrile

Enhancement of characteristics of a functionalized oligophenylene by acid hydrolysis modification

New modified oligophenylene was prepared by acid hydrolysis of a functionalized oligophenylene (OMPA).The latter was obtained by (4-methoxy phenyl) acetonitrile electrochemical oxidation. The resulting modified oligomer (OAC) was characterized by various spectroscopic techniques: NMR, FTIR and UV. The thermal study showed that the modified material exhibited a higher thermal stability compared with OMPA. Further, the optical study revealed that in solution, the emission was blue-shifted when compared with the non-modified oligomer emission and that the optical gap changed from 3.1 eV to 2.75eV. In chloroform solution, photoluminescence was again blue-shifted by 90 nm, which is probably due to an interaction between the oligomer chains.