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The controlled adsorption of molecules of volatile compounds on Langmuir–Schäfer films of tetraphenylporphyrins produces a modification of the film optical anisotropy, as revealed by reflectance anisotropy spectroscopy RAS. These experiments allow a better understanding of the molecular package occurring in the film as well as of its alteration upon the interaction with volatile compounds, helping in the comprehension of the mechanisms responsible for the binding of molecules. The results recommend RAS as a potential transducer technique for chemical sensing.

In this contribution we report the design, preparation and characterization of bichromophoric Langmuir–Schfer multilayer films which enable the simultaneous generation of nitric oxide (NO) and singlet oxygen 1O2 (1Dg). They are achieved by exploiting effective interfacial electrostatic interactions between the floating film of a cationic amphiphilic nitric oxide (NO) photodonor and an anionic porphyrin dissolved in the water subphase. The morphology and the spectroscopic features of the floating films at the water–air interface are inspected by Brewster angle microscopy and UV/Vis reflection spectroscopy, respectively. Multilayer films containing both the chromogenic centres are obtained by horizontal lifting deposition onto hydrophobized quartz substrates and are characterized by steady-state UV/Vis absorption, fluorescence and laser flash photolysis. The anionic porphyrin units are entangled into the films network mainly in their monomeric forms and no significant intra and inter-chromophoric interaction occur in the excited state, preserving the photochemical independency of the two photoactive units in the multilayers. The capability of the bichromophoric films to delivery NO and singlet oxygen, 1O2 (1Dg), under light excitation is unambiguously demonstrated by the direct and in real time monitoring of these transient species using an ultrasensitive electrode and a time-resolved infrared luminescence apparatus, respectively.

In this contribution we report the design, preparation and characterization of bichromophoric Langmuir–Schaefer multilayer films incorporating a tailored nitric oxide (NO) photodonor (1) and an ethylene-bridged zinc porphyrin dimer (2). They are achieved by exploiting the coordination of a pyridine appendage of the NO photodonor to the metal centers of the porphyrin units. Quite uniform floating films at the water–air interface are obtained spreading a mixture of 1:2 in the molar ratio 20:1 as confirmed by Brewster angle microscopy. The floating films are successfully transferred onto quartz slides by horizontal lifting deposition and the resulting hybrid multilayers are characterized by steadystate UV-Vis absorption, fluorescence and laser flash photolysis. The high ratio between the two chromogenic centers prevents the porphyrin aggregation, leading to photoresponsive bichromophoric films able to generate NO and singlet oxygen, 1O2 (1Dg), under the exclusive control of visible light stimuli.

Cu,H2-bis-porphyrin (Cu,H2-Por2), in which copper porphyrin and free-base porphyrin are linked together by an ethano-bridge, was dissolved in chloroform and spread at the air/liquid subphase interface of a Langmuir trough. The bis-porphyrin derivative, floating film was characterized by reflection spectroscopy and the surface pressure of the floating film was studied as a function of the mean area per molecule. When aromatic amines are dissolved in the subphase, an evident interaction between the bis-porphyrin host and the aromatic amine guest is observed. A clear-cut variation of the profile of surface pressure vs area per molecule curve is observed. Reflection spectroscopy highlights that the aromatic amines dissolved in the subphase are able to induce the syn-to-anti conformational switching in the bis-porphyrin derivative. The Langmuir–Schaefer technique has been used to transfer the floating bis-porphyrin film (when using pure water as a subphase) to a surface plasmon resonance (SPR) substrate and the resulting device was able to detect the presence of aniline at concentrations as low as 1 nM in aqueous solution. The high selectivity of the SPR sensing device has been verified by checking the spectral response of the active layer towards other analytes dissolved in the aqueous solutions.

This work reports on the structural and spectroscopic properties, as well as the gas-sensing performance, of ethane-bridged Zn porphyrin dimers (ZnPP) in Langmuir-Schäfer (LS) thin films toward volatile organic compounds in a magneto-optical surface plasmon resonance (MOSPR) configuration. Structural and spectroscopic properties of ethane-bridged ZnPP thin films deposited onto proper Au/Co/Au magneto-optical substrates were inspected in dry air conditions and after exposure to amine vapors by means of IR spectroscopy, scanning probe microscopy, and MOSPR techniques. The molecular organization of the thin films deposited by the LS technique is investigated. The overall results suggest the presence in all cases of mainly the anti-conformer of the investigated porphyrin dimers. The strong interaction between n-butylamine vapors at high concentration and Zn porphyrin thin layers leads to a great conformational change in the porphyrin structure, which is linked to a change in the optical anisotropy of the realized LS layer. © 2012 American Chemical Society., This work has been funded by the European Commission (NMP3-SL-2008-214107-Nanomagma), the Spanish MICINN (CSD 2008-00023, MAT 2008-06765-C02-01/NAN, MAT2010-21228), CSIC (JAE fellowship for E.F.-V.), Comunidad de Madrid (S2009/MAT–1726, S2009/TIC–1476), and FIRB-Futuro in ricerca (Nanoplasmag project- RBFR10OAI0).

Porphyrins are tetrapyrrolic macrocycles with a fascinating and multifarious variegation of properties of essential significance in up-to-date and leading technologies. From a different point of view, the Langmuir–Blodgett technique allows the immobilisation of films with an accurate regulation of molecular organisation and thickness. As a logical upshot, this manuscript concerns a substantial object of consideration in contemporary research, the utilisation of Langmuir–Blodgett multilayers of porphyrins in sensing elements for the detection of analytes in different matrices. Investigations on the morphological, optical, structural and surface characteristics of these films are remarkably related to the significant properties of sensors with the ultimate goal of rationalising the innermost intercourses between the sensing behaviour and the peculiarities and molecular organisation brought about by the deposition method. The integration of the typical electrical and optical characteristics of porphyrins with the potentialities of the Langmuir–Blodgett multilayer has originated not only encouraging projects but has afforded also certainties on the accomplishment of operative chemical sensors.

Tetrapyrrolic macrocycles are largely used in the sensing of various analytes both in liquid and in gaseous phase, but the strong electronic delocalization of this class of molecules makes difficult to realize a selective active layer. To overcome this problem, in the present work it is proposed the synthesis of a supramolecular adduct of zinc oxide nanostructure and a free-base tetra- pyridyl substituted porphyrin. The electronic structure of the two organic/inorganic compounds allows to observe a surface-enhanced Raman scattering (SERS) of the porphyrin vibrational bands. This phenomenon is quenched by the presence of mercuric and cupric ions according to two different mechanisms monitored and explained by means of time resolved fluorescence spectroscopy. It was demonstrated that other substances in complex matrices, such as the food extracts, do not affect the electronic communication between ZnO and porphyrin preserving the SERS effect and minimizing the effect of interfering compounds.

The use of organic materials in the realization of devices for the conversion of solar energy is a hot topic in chemistry, physics, and material science since many years. While the attention is strongly paid toward the synthesis and engineering of new molecules with adequate chemical and physical properties, such materials have to be transferred onto solid substrates, in order to construct functioning devices with high reproducibility and optimizing the performances. Then, deposition technique plays a paramount role in the realization of a photovoltaic device. Moreover, photoactive thin films are often carried out by multilayer stacks with a high spatial organization, and this observation prompted out many researchers to use layer-by-layer, Langmuir–Blodgett (LB), or Langmuir–Schaefer (LS) methods as deposition techniques for the fabrication of such devices. One of the most used class of substances for depositing LB or LS thin films is represented by the porphyrin derivatives whose filmability features can be improved by means of chemical functionalization or by the co-spreading of filmmaker molecules such as octadecylamine or arachidic acid. Furthermore, porphyrins show a very high light harvesting, and they are well-known electron donors, as it happens in the photosynthesis process. In this chapter, several examples of LB and LS film of porphyrin derivatives both used for the realization of photovoltaic devices and for studying the charge transfer processes have been reported.

The mechanisms of interaction between a tetrapyridyl-substituted porphyrin and Hg(II) and Cu(II) ions have been investigated by means of different spectroscopic techniques. Reflection spectroscopy investigations of the porphyrin Langmuir floating film and by polarization modulation infrared (IR) reflection adsorption spectroscopy at the air−water interface provided evidence of the active role played by the pyridyl substituents of the porphyrin in the interaction with the analyte. Such behavior seems to be very selective toward Cu2+ and Hg2+ ions, as demonstrated by the IR measurements in difference mode. UV−vis and IR characterizations suggest a deeply different interaction between the active molecules and the two analytes. In fact, the interaction of Hg2+ ions with the tetrapyrrolic derivative molecules involves both the pyridyl substituents and the central bite of the ring. On the other hand, in the case of Cu2+ ions, spectroscopic evidence suggests that the cupric ions interact with only the porphyrin peripheral substituents. A relevant fluorescence quenching of the Langmuir−Schaefer (LS) film is observed when even a 0.5 nM HgCl2 or 0.5 nM CuCl2 aqueous solution is fluxed on the LS film.

A Langmuir film of bis(zinc octaethylporphyrin) (ZnPP) was characterised at the air–water interface and its syn–anti conformation switching induced upon addition of aromatic amines was studied by infrared and UV–vis reflection spectroscopic methods. The highly specific interaction of ZnPP with aromatic amines was maintained even after the floating film was transferred onto solid supports by the Langmuir– Schaefer (LS) technique, enabling us to selectively sense aromatic amines at concentrations as low as 20 ppb. Furthermore, LS ZnPP active layer selectivity was evaluated in the presence of aliphatic amines.

Ethane-bridged Zn porphyrins dimers (ZnPP) have been deposited by Langmuir-Schäfer (LS) deposition technique onto proper transducer layers for surface plasmon resonance (SPR) and magneto-optical surface plasmon resonance (MO-SPR) characterization techniques performed in controlled atmosphere. This last tool has emerged as a novel and very performing sensing technique using as transducer layers a combination of noble and magnetic layers deposited onto glass substrates. A magnetic actuation allows recording a magneto optical SPR signal which ensures best gas sensing performances in terms of signal to noise ratio, sensitivity and limit of detection parameters. Primary and secondary amines in vapour phase have been used as sensing analytes and a possible explanation of the mechanism as well as of the dynamics of the interaction with the sensing Zn Porphyrin layers is provided. © 2013 Elsevier B.V. All rights reserved., This work has been funded by the European Commission (NMP3-SL-2008-214107-Nanomagma), and by the Italian Ministry of Education (FIRB project-Nanoplasmag). The Spanish MICINN (projects MAPS MAT2011-29194-C02-01 and Funcoat Consolider CSD2008-00023) and Comunidad de Madrid (projects Nanobiomagnet S2009/MAT – 1726 and Microseres S2009/TIC – 1476) are also acknowledged. E.F.-V. thanks CSIC for his JAE fellowship, and the Phantoms Foundation and the nanoICT Coordination Action for the funding of a short stay in Lecce.

We have studied the controlled adsorption of molecules of volatile compounds on thin Langmuir-Blodgett films of porphyrins deposited onto the surface of a quartz microbalance. The modification of the film optical anisotropy has been measured by reflectance anisotropy spectroscopy (RAS), and simultaneously, the amount of adsorbed molecules has been monitored. Optical spectra measured after adsorption of single analytes are interpreted straightforwardly in terms of anisotropies related to the H-like and J-like aggregation modes of porphyrins. By an appropriate selection of analytes, we have then investigated the effect of the exposure to controlled vapor mixtures. The experimental RAS line shape variation with respect to the signal measured before exposure is the sum of the variations produced by single analytes. This shows that the identification of types and even quantities of gases and vapors in gas sensing experiments is possible, and the responses of the sensing layer to single analytes could be listed in a library. © 2011 American Chemical Society.

In this contribution we report the design, preparation and characterization of bichromophoric Langmuir-Schafer multilayer films which enable the simultaneous generation of nitric oxide (NO) and singlet oxygen (1)O(2) ((1)Delta(g)). They are achieved by exploiting effective interfacial electrostatic interactions between the floating film of a cationic amphiphilic nitric oxide (NO) photodonor and an anionic porphyrin dissolved in the water subphase. The morphology and the spectroscopic features of the floating films at the water-air interface are inspected by Brewster angle microscopy and UV/Vis reflection spectroscopy, respectively. Multilayer films containing both the chromogenic centres are obtained by horizontal lifting deposition onto hydrophobized quartz substrates and are characterized by steady-state UV/Vis absorption, fluorescence and laser flash photolysis. The anionic porphyrin units are entangled into the films network mainly in their monomeric forms and no significant intra and inter-chromophoric interaction occur in the excited state, preserving the photochemical independency of the two photoactive units in the multilayers. The capability of the bichromophoric films to delivery NO and singlet oxygen, (1)O(2) ((1)Delta(g)), under light excitation is unambiguously demonstrated by the direct and in real time monitoring of these transient species using an ultrasensitive electrode and a time-resolved infrared luminescence apparatus, respectively.

In this contribution we report the design, preparation and characterization of bichromophoric Langmuir–Schafer multilayer films incorporating a tailored nitric oxide (NO) photodonor (1) and an ethylene-bridged zinc porphyrin dimer (2). They are achieved by exploiting the coordination of a pyridine appendage of the NO photodonor to the metal centers of the porphyrin units. Quite uniform floating films at the water–air interface are obtained spreading a mixture of 1:2 in the molar ratio 20:1 as confirmed by Brewster angle microscopy. The floating films are successfully transferred onto quartz slides by horizontal lifting deposition and the resulting hybrid multilayers are characterized by steady-state UV-Vis absorption, fluorescence and laser flash photolysis. The high ratio between the two chromogenic centers prevents the porphyrin aggregation, leading to photoresponsive bichromophoric films able to generate NO and singlet oxygen, 1O2 (1Δg), under the exclusive control of visible light stimuli.

Reflectance anisotropy spectra of porphyrin thin films (30 monolayers) show a permanent change in their line shape when porphyrins are exposed to some specific analytes (e.g., amines). From this experimental evidence, we concluded that a molecular package adjustment occurred in the film upon interaction with the volatile compound, most likely in the outermost layers. This result is of paramount importance for the consequent application of these films in optical gas-sensors. Consequently, this system could be used as a prototype for optical gas-sensing of aggressive analytes or, more ambitiously, to investigate the porphyrinanalyte interaction. © 2009 Society of Photo-Optical Instrumentation Engineers.

In this contribution we explore the capability of biocompatible nanoparticles (NPs) of cationic amphiphilic cyclodextrins entangling the anionic hydrophilic 5,10,15,20-tetrakis(4- sulfonatophenyl)-21H,23H-porphyrin (TPPS) to facilitate photoinduced energy and electron transfer with suitable donor and acceptor guest molecules, by using a combination of absorption, induced circular dichroism and fluorescence spectroscopy. It is shown that anthracene (AN) and anthraquinone-2-sulfonate (AQS), chosen as appropriate energy donor and electron acceptor, respectively, can be trapped within the NPs network. Fluorescence experiments carried out in the presence and, for comparison, in the absence of NPs provide clear evidence that the amphiphilic NPs strongly encourage singlet-singlet energy transfer from AN to TPPS as well as photoinduced electron transfer from TPPS to AQS. In view of the biocompatibility and drug-carring properties of the NPs used, these results can be of interest from the perspective of designing photo-activated drug delivery systems.

Thin films consisting of two fulleropyrrolidine derivatives 1 or 2 and a water-soluble porphyrin, TPPS4, were prepared by the Langmuir-Schafer (LS, horizontal lifting) method. In particular, a solution of the fulleropyrrolidine in chloroform and dimethyl sulfoxide was spread on the water surface, while the porphyrin (bearing peripheral anionic sulfonic groups) was dissolved into the aqueous subphase. To the best of our knowledge, such a versatile method for film fabrication of fullerene/porphyrin mixed composite films has never been used by other researchers. Evidence of the effective interactions between the two components at the air-water interface was obtained from the analysis of the floating layers by means of surface pressure vs area per molecule Langmuir curves, Brewster angle microscopy, and UV-visible reflection spectroscopy. The characterization of the LS films by UV-visible spectroscopy reveals that in each case the two constituents behave as strongly interacting pi systems. The use of polarized light suggests the existence of a preferential direction of the TPPS4 macrocyclic rings with an edge-on arrangement with respect to the substrate surface, regardless which fulleropyrrolidine derivative is in the composite film. Atomic force microscopy investigations give evidence of morphologically flat layers even for LS transfer at low surface pressures. Photoaction spectra were recorded from films deposited by only one horizontal lifting onto indium-tin-oxide (ITO) electrodes, and the observed photocurrent increased notably with increasing transfer surface pressure for both 1/TPPS4 and 2/TPPS4 composite films. IPCE values are larger for 2/TPPS4 systems in comparison with 1/TPPS4 composite layers. Finally, a nonconventional approach to photoinduced phenomena is proposed by differential spectroscopy in the FT-IR attenuated total reflectance (ATR) mode.

Densely packed hybrid monolayers of amphiphilic cyclodextrins incorporating hydrophilic porphyrins are formed at the air/water interface through electrostatic interaction and can be transferred onto quartz substrates by Langmuir-Scha¨fer deposition. The resulting multilayers exhibit a good response to light excitation as proven by fluorescence emission, triplet- triplet absorption and singlet oxygen photogeneration.

The Langmuir–Schaefer technique has been used to fabricate ordered monolayers of novel heteroleptic double and triple-decker phthalocyanine derivatives. The molecules studied include a double-decker mixed porphyrinate and naphthalocyaninate lanthanum(III) compound and a europium triple-decker molecule where one of the rings is a substituted porphyrin and the two remaining rings are substituted phthalocyanine macrocycles. The materials and their films have been characterised using UV–vis–NIR spectroscopy and electrochemistry. The UV–vis–NIR spectra of the solutions show the expected features corresponding to the aromatic rings present in each molecule. The absorption spectra of LS films show broadenings and important shifts to higher wavelengths when compared to the electronic absorption spectra of solutions or disordered cast films. Thin films are sensitive to electron acceptor gases, such as NOx as observed by modifications in the electronic absorption spectra of the films. These fast and reversible changes can be the basis of optical sensors based on thin films of heteroleptic phthalocyanines (Pc). Cyclic and square wave voltammograms of dichloromethane solutions lead to rich curves where a variety of peaks are observed. The voltammogrames of the corresponding films also reflect the rich electrochemical properties of the studied compounds. Electrochromism has been found with LB and cast films electrodes in KCl and KClO 4 solutions: important changes in the UV–vis–NIR spectra registered in situ simultaneously to the application of the electrical potential have been observed. The rich electrochemistry and the electrochromism observed, opens the possibility of using such films in multicolour electrochromic devices. Films prepared onto ITO glass show characteristic electrochemical responses when exposed to solutions of organic compounds, such as ascorbic and vanillic acid, providing a high degree of cross-selectivity. This effect can be used in the development of arrays of sensors used in electronic tongues. In summary Langmuir–Schaefer films of heteroleptic double and triple-decker phthalocyanines could be of interest at least in three potential applications: thin film electrochromic devices, optical gas sensors and voltammetric sensors.

This work reports on the structural and spectroscopic properties of ethane-bridged Zn porphyrin dimers (1) in Langmuir-Scha¨fer (LS) thin films by combining scanning force microscopy (SFM) with film balance, UV-vis absorption, fluorescence, and nanosecond laser flash photolysis measurements. Results show that depending on the surface pressure the Langmuir films of pure 1 can be arranged in two different condensed phases, whereas SFM of the LS films shows characteristic fractal networks constituted by nanoscopic aggregates. The spectral findings agree with a picture in which 1 is apparently present in the anti conformation but aggregated in a sort of H-type structure whose optical features resemble those of the syn conformer. This type of structure is not responsive to light stimuli. By diluting 1 in arachidic acid the porphyrin aggregation is significantly minimized with 1 exhibiting almost exclusively the anti conformation. As a result the LS films become photoresponsive, showing fluorescence emission and triplet-triplet transient absorption.

Ordered films of porphyrins are routinely obtained by Langmuir–Blodgett technique, with a thickness control at the level of a single monolayer. The study of their optical anisotropy by reflectance anisotropy spectroscopy (RAS) has evidenced an interesting modification of the spectral line shape around the Soret band of the porphyrin layer after a certain critical thickness has been deposited onto the substrate. This finding has been connected to a structural modification of the film, although a detailed model was lacking until now. Recently, a new theoretical study based on the local field interaction has proposed to explain the RAS spectra in terms of the orientation of the molecules in a layer, that would change from layer to layer as the system is assembled. In order to test the model, we have collected new experimental data studying the modification of the optical anisotropy during exposure of the film to a gas (ethanol), mimicking the application for gas sensing analysis. The results show that the model is adequate to describe the real system: reordering of the layer during or after growth originates the anomalous spectra.

Thin films consisting of a fulleropyrrolidine derivative 1 and a novel water-soluble porphyrin 2 were prepared by the Langmuir–Sh+fer (LS, horizontal lifting) method. In particular, a solution of 1 in chloroform and dimethyl sulfoxide was spread on the water surface, while porphyrin 2 (bearing peripheral anionic groups) was dissolved into the aqueous subphase. To the best of our knowledge, such a versatile method of film fabrication for fullerene/porphyrin mixed composite films has never been used before. Evidence of the effective interactions between the two moieties at the air– water interface was obtained from the analysis of the floating layers by means of surface pressure versus area per molecule Langmuir curves, Brewster angle microscopy and UV-visible reflection spectroscopy. The characterisation of the LS films by UV-visible spectroscopy reveals that the two constituents behave as discrete and weakly interacting p systems. The use of polarised light suggests the existence of a preferential direction of the macrocyclic rings with an edge-on arrangement with respect to the substrate surface. Finally, photoaction spectra were recorded from films deposited by only one horizontal lifting onto indium–tin– oxide (ITO) electrodes and the observed photocurrent increased notably with increasing transfer surface pressure.

Meso,meso′ -buta-1,3-diyne-bridged Ni(II), Cu(II) and free base and meso,meso ′-ethene-bridged Ni(II) and free base have been deposited in mixture with arachidic acid as thin films by the Langmuir–Blodgett technique. The floating layers and the film so fabricated have been characterised. Moreover, interesting gas sensing properties have been manifested by the two metallated butadiyne derivatives, evidencing high stability, reversibility, selectivity and sensitivity to nitric oxide. On the contrary, the free bases and the metallated ethene-bridged derivative do not exhibit such behaviour. A rationale of these different characteristics has been proposed on the basis of the existence of different bisporphyrin conformers in the films that reverberates also on the multilayer order and structure.

Langmuir–Blodgett (LB) films of 5,10,15,20-tetrakis-[4-(1-Heptyloxy)phenyl]porphyrin (H2THOPP) in a 1/4 molar ratio with arachidic acid have been deposited onto quartz and silver substrates at the surface pressure of 25 mN/m. A detailed analysis of the Langmuir isotherms is presented. Optical absorption spectra show aggregation of the porphyrins in the LB film. The deposited layers have been characterised by Reflectance Anisotropy Spectroscopy (RAS), showing a large anisotropy signal measured in the Soret band energy region.

Langmuir-Blodgett (LB) films of 5,10,15,20-tetrakis-[4-(1-Heptyloxy)phenyl]porphyrin (H2THOPP) have been deposited onto quartz and silver substrates. The deposited layers (20 monolayers thick) have been characterised by reflectance anisotropy spectroscopy, a technique that recently has been successfully used to study the optical anisotropies of organic materials, For porphyrin LB films, the experimental results show that a large anisotropy signal is measured in the Soret band energy region. We show that this anisotropy is clearly connected to the derivative of the dielectric function of the layer. We propose an interpretation of the derivative-like line shape as due to either strain or similar perturbations on the otherwise symmetric top-layer molecules induced by the lower-lying tilted molecules aligned along a direction related to the growth. (C) 2002 Elsevier Science B.V. All rights reserved.

Ethane-bridged bis-porphyrin derivatives are reported for the selective detection of various analytes in sensing applications. The central metal ion is able to rule specific molecular arrangements upon analyte binding. Three bis-porphyrin compounds: a free base (metal free), Ni complex, and Cu complex, have been tested for histidine detection in aqueous media. Histidine is involved in various biological processes, including such deadly disease as lung cancer. The conformational changes of bis-porphyrins, induced by histidine binding, can be detected by monitoring the Soret band position. The spectroscopic characterization, at the air-water subphase interface, indicates that, in the presence of histidine, the Ni and Cu metallated derivatives undergo conformational changes. This behaviour was confirmed when these two derivatives were deposited onto the solid support by Langmuir-Schaefer (LS) technique. A prototypal Surface Plasmon Resonance (SPR) detection system for histidine based on these two porphyrin LS films was developed. The Cu substituted compound based SPR system allows the histidine sensing down to nanomolar concentration. Furthermore, a SPR response of the Ni bis-porphyrin shows a semilogarithmic dependence on the histidine concentration up to 10−6 M proposing the use of these two porphyrins in a sensor array for the monitoring of histidine levels in plasma.

A highly conjugated dimer of nickel(II) octaethylporphyrin linked by a butadiyne bridge on a meso position has been used for the deposition of Langmuir−Blodgett (LB) films in mixture with arachidic...