STRUCTURE OF A TRANSITION METAL-CONTAINING POLYYNE

Electron diffraction and low-dose, high-resolution imaging techniques have been used to obtain structural information for a rigid-rod polyyne containing platinum atoms directly bonded into the main chain. The high-resolution images show details of the arrangement of the molecular chains into crystallites approximately 50 nm in diameter; dislocations and grain boundaries have also been imaged. A combination of electron diffraction and information derived from image processing of the high-resolution images indicates a unit cell in which parameters of a = 2.08 nm, c = 1.20 nm, and 90-degrees less-than-or-equal-to beta less-than-or-equal-to 93-degrees have been measured and where b has tentatively been assigned as approximately 1.9 nm. The variations in beta relate to improvements in the degree of orientation of the polymer chains that arise from slight stretching of the thin films.