Pressure dependence of the conformational relaxation process in the excited state of tetramethyl-paraterphenyl in solution

✍ Scribed by Ralf Menzel; Horst Lueck; Kevin Jordan; Maurice W. Windsor

• Publisher: Elsevier Science
• Year: 1988
• Tongue: English
• Weight: 429 KB
• Volume: 145
• Category: Article
• ISSN: 0009-2614
• DOI: 10.1016/0009-2614(88)85133-9

✦ Synopsis

Paraterphenyl (PTP) in solution is supposed to undergo a conformational relaxation process from the twisted ground state to the metastable planar configuration of the first excited electronic state. An almost complete steric hindrance of this torsional relaxation process could be detected for the tetrametbyl-(TM-) substituted PTP in rigid solutions at 77 K. To exclude the accompanying temperature effects, the blue-shift of the fluorescence and the accompanying hindrance of the torsional relaxation were studied for TM-PTP in two solvents as a function of pressure up to 345 MPa. Even in glycerol hindrance seems to be incomplete, but its existence is confirmed in general.