Molecular organic films

Molecular organized thin films containing thiophene derivatives. 

The highly oriented molecules in thin organic films such as Langmuir-Blodgett (LB) films and self-assembled monolayers (SAM) [1] are essential for some molecular functions. Non linear optical and opto-electronic properties are two of the most important and interesting functions of these molecular assemblies. In the past more than thirteen years, simulation of the primary process of photosynthesis using such molecular assemblies and its application to molecular photodiodes [2,3] have been one of the main subjects of our laboratory. 

SR Forrest, Ultrathin organic films grown by organic molecular beam deposition and related techniques, Chem. Rev., 97 1793-1896, 1997. 

ORGANIC FILMS Oils or grease (low molecular weight) Vacuum pump fluids Lubricants from air handling unit or other machinery Sweat and oil from personel... 

The study of vapour-deposited organic films has been applied to a large number of molecular systems. However, most of the work has concentrated on the study of the growth and optoelectronic characteristics of planar stacking molecules such as the Pc and polycyclic aromatic compounds based on naphthalene, and perylene. In particular, PTCDA has become extensively studied. 

Figure 3.18. Thin TTF-TCNQ film (thickness 1 um) HV-grown on a KCl(lOO) substrate, (a) Topography and (b) amplitude TMAFM images. The scale is 5 p.m x 5 ]xm. (c) FTIR spectra of the CN stretching mode in neutral TCNQ (powder) and in a TTF-TCNQ thin film (thickness 1 um) HV-grown on KBr(lOO). Reprinted from Surface Science, Vol. 482 85, C. Rojas, J. Caro, M. Grioni and J. Fraxedas, Surface characterization of metallic molecular organic thin films tetrathiaful-valene tetracyanoquinodimethane, 546-551, Copyright (2001), with permission from Elsevier.

Fet us start this section with real-time measurements of the crystallization process of highly ordered thin films of the molecular organic radical / -NPNN grown from the vapour phase on glass substrates (Caro et al, 2000). These films exhibit 2D... 

Figure 5.7. Optical microscope image of a thin film (thickness 2 p.m) of a-p-NPNN grown on a glass substrate (1.6 x 1.0 mm, crossed polarizers). Reprinted from Journal of Crystal Growth, Vol. 209, J. Caro, J. Fraxedas and A. Figueras, Thickness-dependent spherulitic growth observed in thin films of the molecular organic radical p-nitrophenyl nitronyl nitroxide, 146-158, Copyright (2000), with permission from Elsevier.

Figure 5.11. TMAFM image of a thin film (thickness 1 am) of a -/7-NPNN on NaCl(lOO) 1 am x 1 am. Reprinted from Surface Science, Vol. 415, J. Fraxedas, J. Caro, A. Figueras, R Gorostiza andF. SsLnz,Dislocationhollow cores observedon surfaces of molecular organic thin films p-nitrophenyl nitronyl nitroxide radical, 241-250, Copyright (1998), with permission from Elsevier.

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