ISSN:
1573-4803
Source:
Springer Online Journal Archives 1860-2000
Topics:
Mechanical Engineering, Materials Science, Production Engineering, Mining and Metallurgy, Traffic Engineering, Precision Mechanics
Notes:
Abstract The crystal structure of the β-polymorph of metal free phthalocyanine (β-H2Pc) was redetermined from single crystals to obtain precise placements of the hydrogen atoms and a precise model for the X-polymorph (X-H2Pc) for which only limited data from different diffraction techniques are available. Partial occupancy for the hydrogens fixed to the nitrogens in the inner ring was found leading to a highly symmetric phthalocyanine molecule. Careful evaluation of X-ray, electron and neutron diffraction data for X-H2Pc results in an orthorhombic unit cell with a=2.10 nm, b=0.491 nm, c=2.31 nm, space group Pna21 containing four molecules in contrast to a recent determination of Oka and Okada who proposed a monoclinic unit cell with two molecules. As expected the phthalocyanine molecules pack in stacks. The overlap of molecules within one stack matches the current ideas for photosensitive phthalocyanine pigments.
Type of Medium:
Electronic Resource
URL:
http://dx.doi.org/10.1023/A:1018672423851
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