Metal ion induced self-assembly of the rigid ligand 1,4-bis(2,2':6',2 ''-terpyridine-4'-yl) benzene (1) with Fe(II), Co(II), Ni(II) and Zn(II) acetate in aqueous solution results in extended, rigid-rod like metallosupramolecular coordination polyelectrolytes (MEPE-1). Under the current experimental conditions the molar masses range from 1000 g mol(-1) up to 500 000 g mol(-1). The molar mass depends on concentration, stoichiometry, metal-ion and time. In addition, we present viscosity measurements, small angle neutron scattering and AFM data. We introduce a protocol to precisely control the stoichiometry during self-assembly using conductometry. The protocol can be used with different terpyridine ligands and the above-mentioned metal ions and is of paramount importance to obtain meaningful and reproducible results. As a control experiment we studied the mononuclear 4'-(phenyl)2,2':6',2 ''-terpyridine (3) complex with Ni(II) and Zn(II) and the flexible ligand 1,3-bis[4'-oxa(2,2': 6',2 ''-terpyridinyl)] propane (2) with Ni(II) acetate (Ni-MEPE-2). This ligand does not form extended macroassemblies but likely ring-like structures with 3 to 4 repeat units. Through spin-coating of Ni-MEPE-1 on a solid surface we can image the MEPEs in real space by AFM. SANS measurements of Fe-MEPE-1 verify the extended rigid-rod type structure of the MEPEs in aqueous solution

Metal-ion-induced self-assembly in aqueous solution of the rigid ligand 1,4-bis(2,2 0 :6 0 ,2 00terpyridine-4 0 -yl)benzene (1) with Fe(OAc) 2 and Ni(OAc) 2 is investigated with viscosimetry, SANS, and AFM. Ligand 1 forms extended, rigid-rod like metallo-supramolecular coordination polyelectrolytes (MEPEs) with a molar mass of up to 200 000 g mol -1 under the current experimental conditions. The molar mass depends on concentration, stoichiometry, and time. By spin-coating MEPEs on a solid surface, we can image the MEPEs in real space by AFM. Both AFM and SANS confirm the extended rigid-rod-type structure of the MEPEs. As a control experiment, we also studied the flexible ligand 1,3-bis[4 0 -oxa(2,2 0 :6 0 ,2 00terpyridinyl)]propane (2). Ligand 2 does not form extended macro-assemblies but likely ringlike structures with three to four repeat units. Finally, we present a protocol to control the stoichiometry during selfassembly using conductometry, which is of paramount importance to obtain meaningful and reproducible results.

Self-assembly of Fe(2+) ions and the rigid ditopic ligand 1,4-bis(2,2':6',2''-terpyridin-4'-yl)benzene results in metallo-supramolecular coordination polyelectrolytes (MEPE). Sequential self-assembly of MEPE and dialkyl phosphoric acid esters of varying chain length via electrostatic interactions leads to the corresponding polyelectrolyte-amphiphile complexes (PAC), which have liquid-crystalline properties. The PACs have a stratified architecture where the MEPE is embedded in between the amphiphile layers. Upon heating above room temperature, the PACs show either a reversible or an irreversible spin-crossover (SCO) in a temperature range from 360 to 460 K depending on the architecture of the amphiphilic matrix. As the number of amphiphiles per metal ion is increased in the sequence 1:2, 1:4, and 1:6, the temperature of the SCO is shifted to higher values whereas the amphiphile chain length does not have a significant impact on the SCO temperature. In summary, we describe in this article how the structure and the magnetic response function of PACs can be tailored through the design of the ligand and the composition. To investigate the structure and the magnetic behavior, we use X-ray scattering, X-ray absorption spectroscopy, differential scanning calorimetry, faraday-balance, and superconducting quantum interference measurements in combination with molecular modeling.

We have investigated detection thresholds for a foveal blue test light using a Maxwellian view system in 61 normal subjects, 19 patients with Huntington's chorea, 14 patients with Tourette's syndrome, and 20 patients with schizophrenia. Ten measurements were made: The blue test light (1 degree diameter, 500 msec duration) was presented either superimposed on a yellow adaptation field (5 degree diameter) or 500 msec after switching off this field (transient tritanopia effect). In both cases five different background intensities were presented. The only abnormality found was in patients with Huntington's chorea. During adaptation these patients' thresholds are significantly higher than normal (p < 0.005). No change was found in the transient tritanopia effect. Huntington's disease causes degeneration of several different transmitter systems in the brain. Increment threshold testing allows for noninvasive investigation of patients and confirms the involvement of the retina in the degenerative process in Huntington's chorea.

The reactions of the ditopic ligand 1,4-bis(2,2':6',2″-terpyridin-4'-yl)benzene (1) as well as the monotopic ligands 4'-phenyl-2,2':6',2″-terpyridine (2) and 2,2':6',2″-terpyridine (3) with Fe(2+), Co(2+), and Ni(2+) in solution are studied. While the reaction of 1 with Fe(2+), Co(2+), and Ni(2+) results in metallo-supramolecular coordination polyelectrolytes (MEPEs), ligands 2 and 3 give mononuclear complexes. All compounds are analyzed by UV/vis and fluorescence spectroscopy. Fluorescence spectroscopy indicates that protonation as well as coordination to Zn(2+) leads to an enhanced fluorescence of the terpyridine ligands. In contrast, Fe(2+), Co(2+), or Ni(2+) quench the fluorescence of the ligands. The kinetics of the reactions are studied by stopped-flow fluorescence spectroscopy. Analysis of the measured data is presented and the full kinetic rate laws for the coordination of the terpyridine ligands 1, 2, and 3 to Fe(2+), Co(2+), and Ni(2+) are presented. The coordination occurs within a few seconds, and the rate constant increases in the order Ni(2+) < Co(2+) < Fe(2+). With the rate constants at hand, the polymer growth of Ni-MEPE is computed.

Self-assembly of Fe(2+) or Ni(2+) ions and the ditopic ligand 6,6',6''-bis(2-pyridyl)-2,2':4',4'':2'',2'''-quaterpyridine (btpy) through coordinative binding results in rodlike metallosupramolecular coordination polyelectrolytes (Fe-MEPE or Ni-MEPE). Sequential self-assembly with dihexadecyl phosphate (DHP) via electrostatic interactions between MEPE and DHP leads to the corresponding polyelectrolyte amphiphile complex (PAC) with liquid crystalline properties. The MEPE rods are embedded in between the interdigitated DHP layers. Upon heating above room temperature, the Fe-PAC shows an irreversible spin-crossover (SCO) from a diamagnetic low-spin (LS) to a paramagnetic high-spin (HS) state accompanied by a color change from dark blue to pale blue. The SCO is nearly complete (95%) and directly associated with the structure changes induced by the melting of the amphiphilic matrix. The original Fe-PAC architecture does not reassemble upon cooling and remains in a disordered frozen HS state. However, dissolving the heated PAC induces reassembly, and the original dark blue, diamagnetic, ordered material is completely recovered. In comparison to Fe-PAC, Ni-PAC shows the same lamellar structure and the same temperature depended structure changes but has a constant magnetic moment. In contrast to Fe-PAC, in neat Fe-MEPE the SCO depends on the history of the sample and in particular on the amount of included solvent as thermogravimetric analysis, differential scanning calorimetry (DSC), and magnetic measurements indicate. Solid MEPE does not have liquid crystalline properties, and, therefore, the induced structure changes upon heating are constrained by the solid-state architecture, and thus, the SCO in Fe-MEPE is incomplete.

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We investigated the influence of the antiepileptic drugs carbamazepine (CBZ), phenytoin (PHT) and valproic acid (VPA) on different aspects of visual perception in patients with epilepsy by three different methods. (i) The colour arrangement test Farnsworth Munsell D100. (ii) A monitor system generating 24 different Gaussian dots and 24 different vertical sinusoidal gratings. Luminance increments and decrements for achromatic discrimination and four different colours for chromatic discrimination were investigated with four different sizes each adding up to 24 stimuli. (iii) A Maxwellian view system providing a foveal blue test light either superimposed on a yellow adaptation field (increment threshold) or after switching off this field (postadaptation threshold). Five different adaptation levels were investigated. Patients on PHT offered the most abnormalities, particularly in the D100 and in all Gaussian dots recordings. The individual differences between increment and postadaptation threshold (transient tritanopia effect) were significantly elevated at the four higher adaptation levels, whereas no change was found in the increment thresholds and only for the highest luminance level in the postadaptation thresholds. With VPA, chromatic and achromatic increment discrimination was impaired particularly for larger Gaussian stimuli on the monitor system. Valproic acid also induced a consistent increment threshold increase on the Maxwellian view system, an increase of the postadaptation threshold at the highest luminance level and, like PHT, an increase of the threshold differences at level 3 and 4, but not at the highest background level 5. Patients on CBZ provided normal results in all investigations, with the exception of a slight but significant increase in the D100 error score. Sinusoidal gratings turned out to be much less sensitive than Gaussian dots since they remained unchanged in patients on all three drug groups.