Langmuir-Blodgett films and photophysical properties of a C-60-sarcosine methyl ester derivative, C-60(C5H9NO2)

A new C-60-sarcosine methyl ester derivative, C-60(C5H9NO2) (1), was prepared, and its Langmuir films with and without dioctadecyldimethylammonium bromide (DODMAB) were formed at the air/water interface. Pure 1 forms monolayer or multilayer films depending on the experimental conditions. The 1:1 mixed Langmuir film of 1 and DODMAB was transferred onto hydrophilic quartz substrates both in Z and Y type. Macroscopic second-harmonic generation from the mixed LB film was observed, and the second-order molecular susceptibility chi((2)), and hyperpolarizability beta were evaluated to be (2.1 +/- 0.8) x 10(-7) and (1.2 +/- 0.4) x 10(-28) esu. The first observations of room-temperature photoluminescence of 1 from both the mixed LB film and its CHCl3 solution and its fluorescence quenching by concentration and N,N-dimethylaniline (DMA) were reported, Its singlet energy is estimated to be 40.2 kcal/mol. Its fluorescence lifetime in CHCl3 solution is determined to be 1.0 +/- 0.3 ns using the frequency-domain method.