Electron Crystallography of Phthalocyanines

Abstract

<jats:p> It is shown that it is possible to obtain structural information from small (&lt;100 nm) phthalocyanine crystals by using crystallographic direct phasing methods applied to electron diffraction data. This technique is both quantitative and does not suffer from the difficulties associated with high-resolution electron microscopy. Structural information has been obtained from both tetra- and octa chloro-copper phthalocyanines, and the results compared with the hydrogenated and perchloro members of the series. </jats:p>

Chlorosubstituted Copper Phthalocyanines: Spectral Study and Structure of Thin Films

“…Chlorine atoms partially occupy eight positions (0.514/0.486 and 0.516/0.484 for Cl1/Cl2 and Cl3/Cl4, respectively) because the synthesized CuPcCl 4 consists of four regioisomers co-crystallizing in one crystal phase. The distance between two molecules (the mean-square plane through all atoms in the molecule, except hydrogen) in a stack is 3.376 Å, while the stacking angle (the angle between the normal to the plane of the molecule and b-axis) is 21.88 • (27 • as reported in Fryers work [25]). The angle between two molecules in adjacent stacks is 43.76 • .…”

“…CuPcCl 4 crystallizes in a monoclinic crystal system, with a P2 1 /c space group, and Z = 2. It is worth mentioning that different unit cell parameters for CuPcCl 4 were reported by Honigmann et al [31] (a = 26.3 Å, b = 27.8 Å, c = 27.8 Å, β = 94 • , P2 1 /a space group) and Fryer [25] (a = 27.4 Å, b = 27.4 Å, c = 3.65 Å, P4 space group or C2/c space group with β = 90 • ). Although these unit cell parameters differ significantly from those obtained from a single crystal in this work, this does not necessarily mean that CuPcCl 4 has several different polymorphs.…”

“…Haruta et al [24] studied grain boundaries in the thin films of CuPcCl 16 using an aberration-corrected scanning transmission electron microscope combined with electron energy-loss spectroscopy. Fryer [25] determined the parameters of crystal cell of CuPcCl x (x = 4, 8, 16) using the method of electron diffraction.…”

Effect of additives on distributions of lamellar structures in sheared polymer: a study of synchrotron small-angle x-ray scattering

“…The additives are not expected to disperse in the polymer melt at a molecular level. The heterogeneous nucleation thus occurs most likely on the surfaces of additive aggregates or assembles, which are shown in figures 13 and 14 [57][58][59][60]. Since the local areas at which the nucleation actually takes place are much smaller than the sizes of aggregates, the nucleating sites would locally retain the curvature nature of corresponding additive molecules.…”

Fluorination vs. Chlorination: Effect on the Sensor Response of Tetrasubstituted Zinc Phthalocyanine Films to Ammonia

“…Similarly to MPcFx, films of chlorosubstituted MPcCl x can also be deposited by thermal evaporation [27][28][29][30][31]. Parameters of crystal cell of CuPcCl x (x = 4, 8, 16) have been determined by Fryer and co-authors [32] using the method of electron diffraction, while later the single crystal structure of CuPcF 4 -np have been refined [33]. CuPcCl x was shown to demonstrate semiconductor properties with the lower HOMO and LUMO energy levels compared to unsubstituted CuPc [34,35].…”