26 research outputs found
Moleculaire materialen voor de elektronische industrie : van passief naar actief?
No full textA review with 12 refs. on elec. conducting polymers, liq.-crystal polymers, ferromagnetic materials, and non-linear optical polymers. [on SciFinder (R)
Conducting, ferromagnetic, and nonlinear optical properties of polymers
No full textA review with numerous refs. on the elec. conducting, ferromagnetic, and nonlinear optical properties of polymers in relation to their applications in optical and electronic devices. [on SciFinder (R)
Polymers for Electronics and Photonics: conducing ferromagnetic and nonlinear optical properties of polymers
No full textSecond-harmonic generation in centrosymmetric crystals of chiral molecules
No full textFor centrosym. structures of chiral mols., the interaction with circularly polarized light gives nonzero 2nd-order susceptibilities. It is ascribed to transitions that are both magnetic and elec. dipole allowed. Exptl. demonstration is given of 2nd-harmonic generation from centrosym. crystals of R,S-N-acetylvaline (P21/c) using a fundamental wave having elliptic polarization in most parts of the trajectory through the crystal. These results demonstrate the existence of optical activity in the hyperpolarizability term b, similarly to the well-known optical-rotation phenomena in the linear polarizability. [on SciFinder (R)
Poly(1,2-azepines) by the photopolymerization of phenyl azides: a new route to processible conducting polymers
No full textGas-phase photopolymn. of PhN3 afforded poly(1,2-azepinediyl) thin films. The photochem. occurs at the substrate gas-phase interface and the polymer is produced at the surface of the substrate. Upon oxidative doping with I2 or AsF5 these polymers exhibit conductivities ?0.01 S/cm
Sergeants-and-soldiers principle in chiral columnar stacks of disc-shaped molecules with C3 symmetry
No full textExtremely effective cooperative effects operate during the formation of chiral stacks of C3-symmetrical molecules in alkane solvents (a molecule is depicted on the right). The sergeants-and-soldiers principles as well as chiral solvation lead to a preferred helical sense in the columnar aggregates. The amplification of chirality in dynamic systems shows the precision in aggregation
Oligopyrroles by the Ullmann coupling
No full textOligomers were obtained by the Ullmann coupling of N-(tert-butoxycarbonyl)-2,5-dibromopyrrole. The dimerization of 2-bromo-N-(tert-butoxycarbonyl)-5-phenylpyrrole was studied as a model reaction. [on SciFinder (R)
Self-doped water-soluble conducting polymers
No full texta-Terthienyl and pyrrole, substituted with alkylsulfonate side chains, can be polymd. electrochem. without the addn. of a conduction salt. This gives rise to self-doped conducting polymers and are sol. in water in the doped state. [on SciFinder (R)
The x-ray structure and MNDO calculations of a-terthienyl: a model for polythiophenes
No full textThe x-ray structure of a-terthienyl reveals 2 identical, crystallog.-independent mols. in the unit cell. Neighboring thiophene moieties in a-terthienyl are placed antiparallel, while the mol. is almost planar, with torsional angles between the rings of about 6-9 Deg. MNDO calcns. of a-terthienyl show that great care should be taken in using calcns. of this type for geometrical optimizations of polythiophenes
Colorless nonlinear optical D-p-A polymers with sulfones as electron acceptors
No full textColorless side-chain methacrylate copolymers exhibiting relatively narrow charge-transfer bands at 335 nm and second-order optical nonlinearities up to d33 = 4.3 pmV-1 (at 1064 nm) were synthesized and characterized. [on SciFinder (R)
