ABSTRACT:Electrical properties of complex anion radical salts of 7,7,8,8-tetracyanoquinodimethane (TCNQ) with polycations of the following structure:were investigated. It was found that the resistivity of simple salts increases linearly with an increase in the distance between positively charged donor centres S +. For complex salts, the increase in the distance between s+ atoms results in an increase in electrical conductivity up to x=6. The lowest resistivity p 25 =3.110cm-1 and thermal lowest activation energy value E.=0.02leV were found for complexes with x = 6 and the ratio TCNQo ITCNQ 7 = 1.0. High conductivity values determined for these salts are related to the high polarizability of the polymeric cations.

An azo-dye-incorporated polyionene was spin-coated as thin films on silver evaporated glass substrates. The films were used in conjunction with surface plasmon resonance (SPR) spectroscopy to examine the utility of combining these techniques for optical H ϩ -ion sensing. A method suggested by Kano and Kawata was used to enhance the sensitivity of the classical SPR measurements toward absorption detection. With the exposure of the composite polyionene films to HCl vapor, changes in the reflectivity signal were obtained in proportion to the concentration of H ϩ ions and according to the analyzing wavelength. The transformation of the parent azobenzene into the azohydrazone polar form determined the displacement of the absorption band and was the basis for the absorption-enhanced SPR measurements. The difference in the SPR signals for the neutral sample and that exposed to interaction with HCl was most demonstrated for the wavelength at which the sample spectrum changed from being nonabsorbing to absorbing. The results show that chromophoric polyionenes are good materials for the production of sensitive substrates and can be combined with SPR spectroscopy for the optical sensing of aggressive gaseous species.

Communications ADVANCED MATERIALSclearly shows the potential of this technique to improve the performances of molecular based devices. The fabrication of oligomer-based FETs using a metal-included semiconducting a-sexithienylene or pentacene film is currently under way in our laboratory.

The electrical properties oficomplex anion radical salts of 7,7',8,8'-tetracyanoquinodimethane with polycations containing sulfur atoms in the main chain were investigated. The influence of the chemical structure of complex and simple salts on their electrical properties is discussed. Complex salts K, [x, y] containing an odd number of methylene groups between positively charged sulfur atonis show higher electrical conductivity than those with even number of methylene groups between positively charged sulfur atoms. It was found that with simple salts the electrical conductivity increases with the decrease of the distance between s+. For complex salts the electrical conductivity increases if the distance between the donor centers increases. The lowest resistivity values @ = 6.46 R * cm were found with the complex salts K, [5,6], whereas the thermal activatioii energy amounted t o 0.015 eV. Electrical properties of these complexes were compared with that of TCNQ complexes with x-y ionenes. Elektrische Eigenschaften der TCNQ-Komplexsalze von Polykationen mit Schwefelatomen in der HauptketteDie elektrischen Eigenschaften komplcxer Anionradikalsalze von 7,7',8,8'-Tetracyancliinodimethan mit Polykationen, die Schwefelatome in der IIauptlicttc enthalten, wurden untersucht. Der EinflulJ der chemischen Struktur komplexer und einfacher Salzc auf deren elektrische Eigenschaften wird diskutiert. Komplexsalze K, [x, y], die eine ungerade Anzahl von Methylengruppen zwischen den positiv geladenen Schwefcla tomen enthalten, haben hohere elelctrische Leitfahigkeit als solche mit gerader Anzahl von Methylengruppeu. Es wurde festgestellt, daW bei den einfachen Salzen die elektrische Leitfiihigkeit mit abnel.mender Entfernung zwischen den S+-Atomen zuninimt. Bei den Komplexsalzen steigt die elektrische Leitfaliigkcit an, wenn der Abstand zwischen den Donorzentren groaer wird. Die niedrigsten W-iderstandsivertc von = 6,46 R . cm wurden bei dem Komplexsalz I<, [5,6] gefunden, wobci die thermische Aktivierungsenergie 0,015 eV betrug. Die elektrischen Eigenschaften dieser Komplexc werden mit denen von TCNQ Komplexen mit x, y-Ionenen vergliclren. 3AeEmpuuecme csoiicmsa coJteii xowuzexcoe T I l X M c nonuxamuoHaau, coaepxcazqumu amomt cepm e zAasHoii yenu

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The influence of chemical structure of ioncnes containing aromatic rings anti quaternary nitrogen in the unit of polycation chain 011 Lhe electrical properties of TCNQ complex salts was studied. I t was found that the rigidity of the chains of complexes resulting from the presence of aromatic systems in the ionene cliaiti is an important factor influencing the electrical properties of these compounds. Electrical conductivity of these materials is discussed and compared with properties of TCNQ complex salts obtained from bromides of x,y-ionenes. Elektrische Eigenschaften der TCNQ-Komplexsalze von Ionenen mit aromatischen Ringen in der IIauptketteDer EinfluB der chemischen Struktur von Ionenen, die aromatische Ringe und quaternaren Stickstoff in der Monomereinheit der Polykation-Kette enthalten, auf dic elektrischen Eigenschaften von TCNQ-Komplexsalzen wurde untersucht. Es wurde gefunden, daB die Steifheit der Komplexkette infolge der Anwesenheit aromatischer Systeme in der Polykation-Kette einen wesentlichen EinfluB auf die elektrischen Eigenschaften dieser Verbindungen hat. Die elektrische Leitfahigkeit dieser Substanzen wird diskutiert und mit den Eigcnschaften von TCNQ-Komplexsalzen verglichen, die aus Bromiden der x,y-Polykationen crhaltcn wurden. Ssexmpuuecme ceoiicmea TIJXM-icowmemxbix coseii Uoxel-Goa c apofiamuvecli-ufiu yumzamu6 ssasnoii yenu mCCneAOBaH0 BJIHIIHMe XHMMqeCHOfi CTPYKTYPbI EIOHeHOB, COAepmalJJHX apOMaTH9eCKHe qHKJIbI EI 9eTBePTHWIbIi a 3 0~ B MOHOMepHOM 3BeHe qenn IlOJIHKaTHOHa, H a 3JIeKTPH9eCKHe CBOiCTBa TqXM-KOMIIJIeHCHbIX COJIefi. Hai-AeHO, 9TO BCJIeRCTBHe IIpHCyTCTBHR apOMaTtlW.?CKHX CHCTeM B QenH IIOJIHKaTHOHa XeCTKOCTb HOMnJIeKCHOt qenn 3THX BellQ?CTB 0 6 c y m~a e~c a H CpaBHHBaeTCR C CBOiCTBaMH T~-KoMnneKcHbIx C O J I e i , IIOJIyqeHHbIX H3 6pOMHAOB XJ-IIOJIHKaTHOHOB.oKaaMsaeT cyrqeci-seHHoe BnmHHe H a a n e~~p a s e c~~e cBoficma ~T H X coegmemii. 3 n e~~p t l s e c~a a npoBoRaMocTb

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