We have over 12,000 students, from over 100 countries, within one of the safest campuses in the UK


93% of Lancaster students go into work or further study within six months of graduating

Home > Research > Publications & Outputs > Langmuir – Blodgett films incorporating molecul...
View graph of relations

« Back

Langmuir – Blodgett films incorporating molecular wire candidates of ester-substituted oligo(phenylene – ethynylene) derivatives

Research output: Contribution to journalJournal article


Journal publication date15/12/2008
JournalSurface Science
Number of pages5
Original languageEnglish


Langmuir and Langmuir–Blodgett (LB) films of two “wire-like” oligo(phenylene–ethynylene) methyl ester derivatives, namely methyl-4-[(4″-(nonyloxyphenylethynyl)-4′-(phenylethynyl)]-benzoate and methyl-4-[(4″-hexadecyloxyphenylethynyl)-4′-(phenylethynyl]-benzoate (abbreviated as C9BPEB and C16BPEB), have been prepared and characterized. Surface pressure isotherms for both materials have been obtained, with C9BPEB showing more expanded monolayers. An analysis of the reflection spectra of monolayer films at the air–water interface suggests the formation of H-aggregates, and supports an organizational model in which tilt angles of C16BPEB and C9BPEB molecules with respect to the water surface are approximately 70° and 60°, respectively. The sequential transfer of monolayers of these BPEB ester derivatives onto solid substrates results in a Z-type deposition in the case of C9BPEB and Y-type for C16BPEB. The current–voltage (I–V) characteristics of LB monolayers are relatively symmetrical for both films, with the asymmetric contacts more evident in the I–V C16BPEB characteristics.