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Spectral studies of (DB-TTF)(C3H2N3O3) salt-normal vibrations and intramolecular excitations

Barszcz B., Łapiński A., Graja A., Dutkiewicz G., Borowiak T., Flakina A. M., Lyubovskaya R. N.

Scientific Bulletin. Physics / Lodz University of Technology

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2006

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Vol. 26

47-53

EN

Charge transfer salt based on dibenzotetrathiafulvalene (DB-TTF) and the isocyanuric acid anion (C3H2N3O3)- was synthezided and characterized by spectral methods. The (DB-TTF)(C3H2N3O3) salt is a semiconductor with Eg=0.27 eV down to the 100K. The unit cell of (DB-TTF)(C3H2N3O3) salt is monoclinic, space group C2/m, a=23.865(11) Å, b=9.415(4) Å, c=3.701(3) Å, β=96.17(6)°, Z=2. Raman and absorption spectra of the investigated salt were analyzed using the density functional theory. On the base of these calculations an assignement of the vibrational and electronic features was proposed.

PL

Praca zawiera wyniki badań soli (DB-TTF)(C3H2N3O3) w tym dane dotyczące struktury krystalograficznej, przewodnictwa stałoprądowego oraz badań spektroskopowych (spektroskopia rozpraszania Ramana i spektroskopia absorpcyjna w zakresie od podczerwieni do ultafioletu). Widma eksperymentalne zinterpretowano w oparciu o wyniki obliczeń ab initio przeprowadzonych dla molekuły DB-TTF (neutralnej), kationu DB-TTF+ oraz anionu (C3H2N3O3)-. Ponadto przeprowadzono obliczenia wzbudzeń wewnątrzmolekularnych obydwu komponentów soli co pozwoliło na interpretację widm w zakresie UV-Vis-NIR. Analizując szczegółowo drgania normalne stwierdzono obecność dwóch typów molekuł donora w strukturze, ponadto dzięki badaniom przewodnictwa wykazano półprzewodnikowy charakter soli.

2

Spectral studies of new organic conductors based on TTF derivatives with polymeric isocyanuric acid anions

Barszcz B., Łapiński A., Graja A., Flakina A. M., Lyubovskaya R. N.

Materials Science Poland

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2004

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Vol. 22, No. 4

339--346

EN

Spectral investigations of new organic conductors (BEDO-TTF)2(C3H2N3O3) and (DB-TTF) (C3H2N3O3) were performed. Optical absorption spectra in the range of 400-40 000 cm-1 of the powdered salts dispersed in KBr pellets were recorded and analysed. The spectra of (BEDO-TTF)2(C3H2N3O3) are characteristic of organic metals and show small anisotropy, which is typical of quasi-two-dimensional materials. On the other hand, the spectra of (DB-TTF)(C3H2N3O3) are typical of semiconducting materials. The (BEDO -TTF)2(C3H2N3O3) salt undergoes a phase transition at about 120 K. The polarized reflectance spectra of single crystals of (BEDO-TTF)2(C3H2N3O3) were recorded in the range of 600-7000 cm-1, down to 4 K. The frequency dependences of reflectivity were fitted with a Drude model and the transport parameters were evaluated and investigated vs. temperature. An assignment of some vibrational bands in the IR spectra was proposed.

3

Some new findings in t-phase organic conductors

Papavassiliou G. C., Mousdis G. A., Anyfantis G. C., Murata K., Nakanishi T., Li L., Yoshino H., Tajima H., Inoue M., Konoike T., Brooks J. S., Chor E. S., Graf D.

Materials Science Poland

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2004

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Vol. 22, No. 4

365--372

EN

Some new findings concerning the structural, optical, transport, and magnetotransport properties of t-phase organic conductors, based on the donor molecules ethylenedioxy-S,S-dimethylethylenedithiotetrathiafulvalene, ethylenedioxy-R,R-dimethylethylenedithio-tetrathiafulvalene, pyrazino-S,S-dimethylethylenedithio- tetrathiafulvalene, pyrazino-R,R-dimethylethylenedithio-tetrathiafulvalene, pyrazino-r-dimethylethylenedithio- tetrathiafulvalene, pyrazino-S,S-dimethylethyledithio-diselenadithiafulvalene, pyrazino- r-methylethylenedithio-tetrathiafulvalene, and pyrazino-r-methylethylenediseleno-tetrathiafulvalene are described. Some similarities and differences in their properties are discussed.

4

Reflectivity spectra of some conducting BETS salts

Kaplunov M. G., Kushch N. D., Krasnikova S. S.

Materials Science Poland

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2004

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Vol. 22, No. 4

359--364

EN

We have measured the polarized reflectivity spectra of three BETS-based organic metals with the a-phase structure: a-(BETS)2NH4Hg(SCN)4 (I), a-(BETS)2TlHg(SeCN)4 (II), and a-(BETS)2Cu5I6 (III) in the range of 600-6500 cm-1. The spectra exhibit a metallic-type reflection with the plasma edge about 4000-5000 cm-1 and high reflectivity at low frequencies. The electron-vibrational bands observed in the range of 1200-1400 cm-1 are due to the interaction of the intramolecular vibrational modes of BETS with conduction electrons.

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Optical properties of the one-dimensional organic conductors ß-(EDT-TTF-I2)2(Pb5/6 1/6I2)3 and ß-(EDT-TTF-I2)2(Pb2/3+xAg1/3-2x xI2)3, x = 0.05

Olejniczak I., Gromadziński B., Graja A., Devic T., Batail P.

Materials Science Poland

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2004

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Vol. 22, No. 4

347--352

EN

We report the room-temperature polarized infrared reflectance spectra of two radical cation salts based on halogenated TTF and two-dimensional polymeric iodoplumbate or Ag-doped iodoplumbate anions. These salts were ß-(EDT-TTF-I2)2(Pb5/6a1/6I2)3 and ß-(EDT-TTF-I2)2(Pb2/3+xAg1/3-2x??xI2)3, where x = 0.05 and a is a vacancy. Both materials display a metallic response, characteristic of quasi-onedimensional organic conductors. The ß-(EDT-TTF-I2)2(Pb2/3+xAg1/3-2x??xI2)3 salt, with x = 0.05 is partly transparent along the lowest conductivity direction in the infrared frequency range. The single-crystal polarized absorption spectrum recorded in this direction displays a number of vibrational features related to the intramolecular modes of the EDT-TTF-I2 molecule, which are assigned using available normal mode calculations. In addition, the absorption spectrum of the ß-(EDT-TTF-I2)2(Pb2/3+xAg1/3-2xaxI2)3 material dispersed in a KBr pellet is reported and discussed.

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A new organic metal with thedithiooxalato - bridged anion network β″-ET)2{[NMe3Ph]NaCr(C2S2O2)3(MeCN)}

Zhilyaeva E. I., Shilov G. V., Bogdanova O. A., Lyubovskaya R. N., Lyubovskii R. B., Lyubovskaya R. N., Ovanesyan N. S., Aldoshin S. M., Train C., Gruselle M.

Materials Science Poland

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2004

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Vol. 22, No. 4

565--569

7

20 Years of Reticulate Doping-Beyond Conductive Properties

Jeszka J.

Polish Journal of Chemistry

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2002

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Vol. 76 / nr 2-3

201-218

EN

The most interesting results obtained during 20 years of studies on reticulate doped polymers preparation and properties are reviewed. All developed methods of preparation are described and the influence of different parameters on the properties of obtained materials is briefly discussed. The stress is put not so much on the electrical properties but on the aspects of preparation and on the properties, which are interesting but deserved less attention till now like structure, morphology and composition of the microcrystals and their transformations, optical, magnetic and other properties.