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1 The most comprehensive studies on the spectral sensitization of organic semiconductors by dyes were performed for poly( N -vinylcarbazole) (PVK) and poly( Nepoxypropylcarbazole) (PEPK) using cationic, anionic, and nonionic dyes [1][2][3]. The cationic dyes xanthene, triarylmethane, and polymethine have been the main subjects of study concerning the mechanism of spectral sensitization. However, in studying the sensitization of organic semiconductors by cationic dyes, little attention was given to the effect of the dye anion on the sensitization properties of the molecule as a whole. We suggested using as sensitizers for organic semiconductors cationic triphenylmethane (TPM) dyes with complex anions containing metal [4]. Such cationic dyes of the formula ä + , where ä + is the dye cation and is the complex anion containing metal M and organic or inorganic ligand L, are named ternary complexes or ion associates [5].The aim of this work was to study ternary complexes of triphenylmethane dyes as sensitizers for PEPK and diphenylhydrazones of benzaldehydes (hereinafter referred to as hydrazones) and to reveal the influence of the complex anion on the sensitizing activity of the dye. EXPERIMENTAL Ternary complexes of the TPM dyes Brilliant Green, Malachite Green, Methyl Violet, and Crystal Violet, with the complex anions , , , , and [Tl(PC) 3 ] 3-(where PC is pyrocatechol) were syn-1 E-mail: see@ipc.tsc.ru ML [ ] n -ML [ ] n -SbCl 6 -GaCl 4 -InCl 4 -TlCl 4 -thesized according to procedures described earlier [6-9]. PEPK prepared by the reaction of N -epoxypropylcarbazole polymerization in an alkaline medium [10] was purified by reprecipitation from toluene into hexane and dried in vacuum. p -Diethylaminobenzaldehyde N , N -diphenylhydrazone (H-1) and p -bromobenzaldehyde N , N -diphenylhydrazone (H-2) were prepared according to a known procedure [11], doubly recrystallized from ethanol, and dried in vacuum. Polycarbonate of the PK-6 brand chosen as a polymeric binder was purified by reprecipitation from chloroform into hexane and dried in vacuum.Electronic absorption spectra of starting TPMD and the ternary complexes in chloroform and PEPK or polycarbonate films with hydrazones were recorded on a Specord M40 spectrophotometer.The sensitizing activity of the starting TPM dyes and their ternary complexes with respect to PEPK and hydrazones was estimated from the values of the photosensitivity S 0.1 and the residual potential U res for samples of a single-layer electrophotographic material (hereafter referred to as samples), which represented a layer of a photosensitive composition applied onto an aluminum substrate by dipping-roller coating. Photosensitive compositions consisted of (wt %) PEPK (99.5-97.0) and a dye (0.5-3.0) or a hydrazone (48.5), PK-6 (50.0), and a dye (1.5). The photosensitivity and the residual potentials were determined by the method of potential photodecay using a laboratory sensitometer, which permitted testing the samples in the electrophotographic mode at positive and negative charging of the sur...

Spectral-luminescent properties of γ-pyrilocyanines and their heteroanalogs with modified complex anions have been studied. It was shown that the fluorescence quantum yield in the series pyrilo-, thiapyrilo-, and selenopyrilocyanine decreased for mono-and trimethinecyanines as well as through substitution of TlCl 4 − for. This is likely due to the increased probability of singlet-triplet transfers under the influence of heavy atoms.Introduction. Polymethine dyes are unique transformers of visible and IR light [1] and are widely used as photosensitizers [2,3], lasing materials [4,5], photoresists, and new media for information storage. Relationships between the chemical structure of the dye and its spectral-luminescent properties must be established in order to discover effectively dyes that are capable of purposeful transformation of light energy. This requires a comprehensive approach to the study of spectral-luminescent properties, e.g., investigation of electronic absorption spectra, luminescence spectra, luminescence quantum yields, excited state lifetimes, and other properties.The goal of our work was to study features of the spectral-luminescent properties of γ-pyrilocyanines and their heteroanalogs as a function of the structure of the dye anion and cation.Experimental. We investigated pyrilium, thiapyrilium, and selenopyrilium dyes of general formula R + Y -:

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