Silver(I) and zinc(II) complexes with N,N 0-bis(trans-cinnamaldehyde)ethane-1,2-diamine (EnCinn) have been synthesized and characterized by elemental analysis, simultaneous thermogravimetric and differential thermal studies (TG-DTA), infrared (IR), 1 H and 13 C nuclear magnetic resonance (NMR) spectroscopic measurements and electrospray ionization quadrupole time-of-flight mass spectrometry (ESI-QTOF-MS). Crystal and molecular structure descriptions were performed based on powder X-ray diffraction data. The AgEnCinn complex has a polymeric structure where the ligand bridges between two Ag(I) ions, while the ZnEnCinn complex has a monomeric structure with EnCinn acting as chelating ligand. Antimycobacterial assays over Mycobacterium tuberculosis showed the activity of the Ag(I) complex with Minimum Inhibitory Concentration (MIC) value of 22.7 lmol L À1 , while the Zn(II) complex was shown to be inactive over the same experimental conditions.
Recebido em 29/05/2019; aceito em 30/07/2019; publicado na web em 21/10/2019 TEMPERATURE EFFECTS ON RAMAN SPECTRA OF PEDOT AND MEH-PPV CONDUCTING POLYMERS. The present work shows the temperature dependence of the Raman spectra of two conjugated polymers: poly[2-methoxy-5-(2-ethylhexyloxy)-1,4-phenylenevinylene] (MEH-PPV) and poly(3,4-ethylenedioxythiophene)-poly(styrenesulfonate) (PEDOT:PSS). In situ resonance Raman spectra of PEDOT from 77 to 423 K at 633 nm and of MEH-PPV from 77 to 473 K at 785 nm suggest that, for both polymers, as the temperature increases there is a decrease in the chain conjugation length. Raman bands of PEDOT assigned to the ν sim C α-C β are the most sensitive to temperature while bands due to oxyethylene rings do not show significant shifts in this temperature range. Raman and FT-IR spectra of MEH-PPV recorded above the thermal decomposition temperature provide some insights about the thermal degradation.
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