Influence of substituents and chain length on the optical properties of poly(p-phenylenevinylene) oligomers
β Scribed by William B. Davis; Michael R. Wasielewski; Mark A. Ratner
- Publisher
- John Wiley and Sons
- Year
- 1999
- Tongue
- English
- Weight
- 195 KB
- Volume
- 72
- Category
- Article
- ISSN
- 0020-7608
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β¦ Synopsis
Electronic-structure calculations based upon the PariserαParrαPople semiempirical Hamiltonian were applied to short-chain oligomers of the conducting Ε½ . Ε½ . polymer poly p-phenylenevinylene PPV to study the effects of appending methoxy groups along the backbone as well as pushαpull nitro and amino groups at the ends of the oligomers. Optical absorption spectra were calculated utilizing configuration interaction methods at the single-excitation level, and the nonlinear optical properties of the pushαpull oligomers were studied using the sum-over-states approach. In short-chain oligomers, the calculated electronic and optical properties are controlled by the nature of the pendant groups. However, in the longest oligomers studied, these molecular properties are relatively insensitive to any of the studied modifications.
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