Abstract
The oxidative electrochemistry of the cofacially joined phthalocyanine polymer [Si (Pc)O]n to yield molecular "metals" with tunable band filling is described. Initial doping (oxidation) of orthorhombic [Si (Pc)O]n is accompanied by a rearrangement to a tetragonal crystal structure. Once in the tetragonal crystal structure, the conduction band filling can be continuously varied (i.e. doping is homogeneous) over a broad range in y for {[Si (Pc)O]Xy∼n. For example, materials incorporating BF-4 as the counterion can be tuned between y = 0.0 and y = 0.50. In fact, the maximum doping level obtainable with a given counterion is largely a function of anion size. Charge transport, optical, and magnetic studies of the {[Si (Pc)O] (BF4)y∼n materials reveal an evolution in properties from insulator/semiconductor-like to metal-like with increasing y and an abrupt insulator-to-metal transition at y ≈ 0.20. This change at y ≈ 0.20 appears to be an Anderson-like transition from localized (disordered) states to delocalized states. Physical measurements on {[Si (Pc)-O] (SO4)y∼n show no evidence of exceptional electronic effects attributable to the dinegative counterion.
Original language | English |
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Pages (from-to) | 15-24 |
Number of pages | 10 |
Journal | Synthetic Metals |
Volume | 29 |
Issue number | 2-3 |
DOIs | |
Publication status | Published - Mar 21 1989 |
ASJC Scopus subject areas
- Electronic, Optical and Magnetic Materials
- Condensed Matter Physics
- Mechanics of Materials
- Mechanical Engineering
- Metals and Alloys
- Materials Chemistry