The valence electronic structure of isotactic polystyrene revisited

✍ Scribed by E. Ortí; S. Stafström; J.L. Brédas

• Publisher: Elsevier Science
• Year: 1989
• Tongue: English
• Weight: 561 KB
• Volume: 164
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(89)85022-5

✦ Synopsis

We present a comparison between the experimental UPS spectrum of polystyrene and a theoretically simulated spectrum derived from valence effective Hamiltonian (VEH) calculations. The calculations arc carried out on a stereoregular helical isotactic polystyrene chain where the bonds joining the backbone to the phenyl groups are trans relative to the backbone (defining an isotactic polystyrene conformation denoted i-PS ). This conformation is different from that considered in a previous work ( BrCdas and Street (1985) ) where the backbone-phenyl bonds were gauche with respect to the backbone (i"-PS conformation). The theoretical tiPS spectra produced by the i-PS and I"-PS conformations present subtle yet significant differences which, when comparison is made to experiment, all point in favor of the i-PS conformation considered in this work. This resolves some of the discrepancies between theory and experiment from previous work.