Lattice Imaging of Electro-Optically Active Poly(nonylbithiazole) (PNBT)

Structural Characterization of Electrooptically Active Poly(nonylbithiazole)

“…Samples subjected to hydrostatic pressure saw a very slight increase in degree of crystallinity (from 34% to 37%) and no change in crystal size (Δ D 100 = 7 nm). Note that the 6 ± 1 nm crystal size calculated by WAXS for solvent-cast red PNBT is significantly smaller than the 13 ± 6 nm previously measured by low-dose high-resolution transmission electron microscopy (HRTEM) 7 Wide-angle X-ray scattering (WAXS) patterns of green, red, and yellow PNBT samples. 2 Correlation Distances ( d Spacings, nm) of Yellow, Red, and Green PNBT Samples Measured by Wide-Angle X-ray Scattering (WAXS) green PNBTred PNBTyellow PNBT 2.43 ± 0.3 2.36 ± 0.6 1.97 1.23 ± 0.2 1.24 ± 0.2 0.82 ± 0.2 0.84 ± 0.2 0.358 ± 0.03 0.361 ± 0.01 3 Average Degree of Crystallinity ( X c ) and Crystal Size along (100) (Δ D 100 ) for Red and Green PNBT Samples colorprocessing method X c (%)Δ D 100 (nm) red solvent-cast 44 ± 14 6 ± 1 green solvent-cast 60 ± 35 10 ± 2 green annealed 22 ± 1 29 ± 4 …”

“…Such piezochromism has also been observed in bulk red samples of poly(nonylbithiazole- co -ethynylene) (PENBT), which become metallic-green under similar applied pressures. Since the polymer chains tend to align parallel to the plane of the substrate, the applied pressure is expected to lead to closer π-stacking of thiazole rings between neighboring chains and increased planarity along the backbone.…”

Defect-mediated curvature and twisting in polymer crystals

“…The simulations were performed for varying chain length N (typically [3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20] to simulate different defect densities. To isolate the dislocation, we constructed superlattices that topologically trap the defect into a larger, periodic unit cell.…”

“…The impact of structural defects on the optoelectonic and mechanical properties of inorganic materials is fairly well established. [10][11][12][13][14][15][16][17] Such deformations disrupt the three-dimensional periodicity of the crystal, and are thus of fundamental scientific interest and have important practical implications. [7][8][9] Characteristic deformation modes which have been observed at high resolution in polymer crystals include bending and twisting (Fig.…”

Genetic Algorithms For Structure Prediction Of New Bithiazole Molecular Crystals Methodology And Applications

“…Bithiazoles and their derivatives are of great interest because of their potential applications such as ligands for metals [22,23] and biological activities of their complexes, which show antibacterial, antifungal, antiflammatory, and antitumeractivities [24][25][26][27]. They are also useful as electrochromic materials, photoluminescence, and semiconductor devices [28][29][30][31][32][33][34]. Geometry optimization of bithizaole molecules were perform using the B3LYP hybrid density functional method of theory with the STO-3g, 3-21G and 6-311G** basis sets.…”