Molecular photonic device

The biaryls are useful in rational designing functional molecules and materials. The large steric hindrance and the semirigid structure with restrict rotation provided various functional biaryls, such as arylporphyrins [162,170], molecular-scale motors rotate by chemical power or light [73,163], a photoswitchable electron transfer aromatic compounds for the design of molecular photonic devices [171,172],a stable thioaminyl radicals [173],phenylnitroxide-substitut-ed Zn(II) porphyrins [174], and polycyclic aromatic compounds [175-177]. 

Molecular Photonic Devices - Controlling Light with Supermolecules It is... 

D. Holten, D.F. Bocian, J.S. Lindsey, Probing Electronic Communication in Covalently Linked Multiporphyrin Arrays. A Guide to the Rational Design of Molecular Photonic Devices , Acc. Chem. Res., 35,57 (2002)... 

A current challenge is the development of efficient strategies for the design of switchable nonlinear optical (NLO) materials. The ability to switch the NLO activity of a molecule on and off is of relevance for the development of molecular photonic devices, as those properties can be... 

Holten, D. Bocian. D.F. Lindsey. J.S. Probing electronic communication in covalently linked multipoiphyrin arrays. A guide to the rational design of molecular photonic devices. Acc. Chem Res. 2002, 35. 57. 

In this chapter we have described various types of diarylethene derivatives with different functionalities. The characteristic features of the photochromic reactions, such as switch of Ji-conjugation length, geometrical structure changes, and electric as well as vibrational structure changes, can find applications in various molecular photonics devices. 

The substituted five-ring OPVs have been processed into poly crystal line thin films by vacuum deposition onto a substrate from the vapor phase. Optical absorption and photolumincscence of the films are significantly different from dilute solution spectra, which indicates that intermolecular interactions play an important role in the solid-state spectra. The molecular orientation and crystal domain size can be increased by thermal annealing of the films. This control of the microstruc-ture is essential for the use of such films in photonic devices. 

The FPI principle can also be used to develop thin-film-coating-based chemical sensors. For example, a thin layer of zeolite film has been coated to a cleaved endface of a single-mode fiber to form a low-finesse FPI sensor for chemical detection. Zeolite presents a group of crystalline aluminosilicate materials with uniform subnanometer or nanometer scale pores. Traditionally, porous zeolite materials have been used as adsorbents, catalysts, and molecular sieves for molecular or ionic separation, electrode modification, and selectivity enhancement for chemical sensors. Recently, it has been revealed that zeolites possess a unique combination of chemical and optical properties. When properly integrated with a photonic device, these unique properties may be fully utilized to develop miniaturized optical chemical sensors with high sensitivity and potentially high selectivity for various in situ monitoring applications. 

We have shown that redox chromophores organized in LB films with resped to their orientation, alignment, or electronic interactions make very useful and specific photoresponses such as amplified fluorescence quenching, photocurrents controlled at the molecular level, photoinduced anisotropic eledrochromism, and photochemically modulated second harmonic generation. These results may contribute to facilitate the design and construction of novel photonic devices in the near future. 

The results presented above illustrate how combining the design of NLO active molecules with the manipulation of selective intermolecular interactions may produce novel NLO materials. Bringing together two basic features of supramolecular chemistry -molecular recognition and self-organization- with the optical properties of the components, opens ways towards the design of supramolecular photonic devices. 

Novel Molecular Photonics Materials and Devices Toshihiko Nagamura... 

The LB deposition is one of the best methods to prepare highly organized molecular systems, in which various molecular parameters such as distance, orientation, extent of chromophore interaction, or redox potential can be controlled in each monolayer. We have been studying photophysical and photochemical properties of LB films in order to construct molecular electronic and photonic devices. The molecular orientation and interactions of redox chromophores are very important in controlling photoresponses at the molecular level. Absorption and fluorescence spectra give important information on them. We have studied photoresponses, specific interactions, and in-plane and out-of-plane orientation of various chromophores in LB films [3-11], In addition to the change of absorp-... 

---