Abstract
Langmuir-Blodgett (LB) films formed of some discotic liquid crystals, namely 3,4,9,10-tetra-(n-alkoxy-carbonyl)-perylenes, mixed with arachid acid have been studied. The absorption and fluorescence spectra were recorded. The results obtained have led to conclusions about formation of self-aggregates of dye molecules both in ground and excited states at the air-solid substrate interface. It was found that some fraction of J-aggregates can be created in the ground state. In the excited state, mostly excimers appear and the number of this kind of aggregates depends on the length of the alkyl chains substituted to the perylene core, as well as on the dye concentration and the number of layers in LB films.
[1] Organic Light Emitting Devices. Synthesis, Properties and Applications, edited by K. Muellen and U. Scherf, Wiley-VCH, Weinheim, 2006. Search in Google Scholar
[2] S. Benning, H.S. Kitzerow, H. Bock, and M.F. Achard, “Fluorescent columnar liquid crystalline 3,4,9,10-tetra-(n-alkoxycarbonyl)-perylenes”, Liq. Cryst. 27, 901–906 (2000). http://dx.doi.org/10.1080/0267829005004384210.1080/02678290050043842Search in Google Scholar
[3] R. Stolarski and K. Fiksiński, “Fluorescent perylene dyes for liquid crystal displays”, Days and Pigments 24, 295–303 (1994). http://dx.doi.org/10.1016/0143-7208(94)87005-510.1016/0143-7208(94)87005-5Search in Google Scholar
[4] E. Mykowska and D. Bauman, “Perylene-like dyes in liquid crystalline media”, Z. Naturforsch. 51a, 843–850 (1996). 10.1515/zna-1996-0708Search in Google Scholar
[5] G. Roberts, Langmuir-Blodgett Films, Plenum Press, New York, 1990. 10.1007/978-1-4899-3716-2Search in Google Scholar
[6] A. Ulman, An Introduction to Ultrathin Organic Films — from Langmuir-Blodgett to Self-Assembly, Academic Press, New York, 1991. 10.1016/B978-0-08-092631-5.50009-9Search in Google Scholar
[7] M.C. Petty, Langmuir-Blodgett Films — An Introduction, Cambridge University Press, Cambridge, 1996. 10.1017/CBO9780511622519Search in Google Scholar
[8] R. Hertmanowski, Ł. Chudziński, T. Martyński, P. Stempniewicz, E. Wolarz, and D. Bauman, “Spectroscopic studies of Langmuir-Blodgett films of 3,4,9,10-tetra-(heptyloxycarbonyl)-perylene and its mixtures with a liquid crystal”, Liq. Cryst. 31, 791–800 (2004). http://dx.doi.org/10.1080/0267829041000168158210.1080/02678290410001681582Search in Google Scholar
[9] R. Hertmanowski, A. Biadasz, T. Martyński, and D. Bauman, “Optical spectroscoppy study of 3,4,9,10-tetra-(n—alkoxy-carbonyl)-perylenes in Langmuir-Blodgett films”, J. Mol. Struct. 646, 25–33 (2003). http://dx.doi.org/10.1016/S0022-2860(02)00707-X10.1016/S0022-2860(02)00707-XSearch in Google Scholar
[10] R. Hertmanowski, T. Martyński, and D. Bauman, “Alignment of molecules in Langmuir and Langmuir-Blodgett films of binary mixtures of 3,4,9,10-tetra-(n-alkoxy-carbonyl)-perylenes with a liquid crystal”, J. Mol. Struct. 741, 201–211 (2005). http://dx.doi.org/10.1016/j.molstruc.2004.10.12110.1016/j.molstruc.2004.10.121Search in Google Scholar
[11] G.L. Gaines, Jr., Insoluble Monolayers at Liquid-Gas Interfaces, Interscience Publishers, New York, 1966. Search in Google Scholar
[12] J. Tanaka, “The electronic spectra of aromatic molecular crystals. II. The crystal structure and spectra of perylene”, Bull. Chem. Soc. Jpn. 36, 1237–1249 (1963). http://dx.doi.org/10.1246/bcsj.36.123710.1246/bcsj.36.1237Search in Google Scholar
[13] J. Ferguson, “Absorption and emission spectra of the perylene dimer”, J. Chem. Phys. 44, 2677–2683 (1966). http://dx.doi.org/10.1063/1.172711010.1063/1.1727110Search in Google Scholar
[14] D. Bauman, R. Hertmanowski, E. Chrzumnicka, and T. Martyński, “Fluorescent discotic liquid crystals in Langmuir-Blodgett films for application in organic emitting diodes”, Proc. SPIE 5947, 594713 (2005). http://dx.doi.org/10.1117/12.62510410.1117/12.625104Search in Google Scholar
[15] R. Hertmanowski, E. Chrzumnicka, T. Martyński, and D. Bauman, “Self-aggregates formation of 3,4,9,10-tetra-(n-alkoxy-carbonyl)-perylenes in Langmuir-Blodgett films”, J. Lumin. 126, 323–332 (2007). http://dx.doi.org/10.1016/j.jlumin.2006.07.02710.1016/j.jlumin.2006.07.027Search in Google Scholar
[16] A.G. Vitukhnovsky, M.I. Sluch, J.G. Warren, and M.C. Petty, “The fluorescence of perylene-doped Langmuir films”, Chem. Phys. Lett. 173, 425–429 (1990). http://dx.doi.org/10.1016/0009-2614(90)87228-J10.1016/0009-2614(90)87228-JSearch in Google Scholar
[17] D. Weiss, R. Kietzmann, J. Mahrt, B. Tufts, W. Storck, and F. Willig, “E-excimer and Y-type luminescence of perylene dimers in a Langmuir-Blodgett film at 1.5 K”, J. Phys. Chem. 96, 5320–5325 (1992). http://dx.doi.org/10.1021/j100192a02710.1021/j100192a027Search in Google Scholar
[18] A.S. Davydov, Theory of Molecular Excitons, Mc Graw-Hill Book Company, Inc., New York, 1962. Search in Google Scholar
[19] M. Kasha, H.R. Rawls, and M. Ashraf El-Bayoumi, “The exciton in molecular spectroscopy”, Pure Appl. Chem. 11, 371–392 (1965). http://dx.doi.org/10.1351/pac19651103037110.1351/pac196511030371Search in Google Scholar
[20] D. Moebius, “Scheibe aggregates”, Adv. Mater. 7, 437–444 (1995). http://dx.doi.org/10.1002/adma.1995007050310.1002/adma.19950070503Search in Google Scholar
[21] A. Miyata, D. Heard, Y. Unuma, and Y. Higashigaki, “Three types of aggregates of spiropyran with long and short hydrophobic alkyl chains”, Thin Solid Films 210/211, 175–177 (1992). http://dx.doi.org/10.1016/0040-6090(92)90202-M10.1016/0040-6090(92)90202-MSearch in Google Scholar
[22] Z. Salamon and H. Baessler, “Fluorescence properties of perylene aggregates in a polymer matrix (PMMA)”, Chem. Phys. 100, 393–400 (1985). http://dx.doi.org/10.1016/0301-0104(85)87065-810.1016/0301-0104(85)87065-8Search in Google Scholar
[23] A.G. Vitukhnovsky, M.I. Sluch, J.G. Warren, and M.C. Petty, “Observation of perylene excimers in Langmuir-Blodgett films”, Chem. Phys. Lett. 184, 235 (1991). http://dx.doi.org/10.1016/0009-2614(91)87193-F10.1016/0009-2614(91)87193-FSearch in Google Scholar
[24] J. Mahrt, F. Willig, W. Storck, D. Weiss, R. Kietzmann, K. Schwarzburg, B. Tufts, and B. Troesken, “Luminescence and configurations of perylene dimers in a Langmuir-Blodgett film”, J. Phys. Chem. 98, 1888–1894 (1994). http://dx.doi.org/10.1021/j100058a02910.1021/j100058a029Search in Google Scholar
[25] M.I. Sluch, A.G. Vitukhnovsky, and Lu Ande, “Fluorescence of perylene-4-octadecanon in Langmuir-Blodgett films”, Thin Solid Films 248, 230–233 (1994). http://dx.doi.org/10.1016/0040-6090(94)90016-710.1016/0040-6090(94)90016-7Search in Google Scholar
[26] S. Akimoto, A. Ohmori, and I. Yamazaki, “Dimer formation and excitation relaxation of perylene in Langmuir-Blodgett films”, J. Phys. Chem. 101, 3753–3758 (1997). Search in Google Scholar
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