PL EN


Preferences help
enabled [disable] Abstract
Number of results
2017 | 131 | 4 | 925-927
Article title

Magnetic Specific Heat of Anion-Radical Salt [Ni(bipy)₃](TCNQ)₄·(CH₃)₂CO at Very Low Temperatures

Content
Title variants
Languages of publication
EN
Abstracts
EN
Thermodynamic studies of the anion-radical salt system [Ni(bipy)₃](TCNQ)₄·(CH₃)₂CO, where TCNQ is 7,7',8,8'-tetracyano-quinodimethane, are reported. The anion-radical salt systems based on TCNQ belong to a material class in which the arrangement of the anion-radical salt has considerable impact on the charge transfer and magnetic properties. The crystal structure of the studied compound consists of [Ni(bipy)₃]⁺² cations containing Ni⁺² ions and four types of crystallographically independent anion-radicals TCNQ^{·-} (A, B, C and D). These TCNQ^{·-} radicals form two different types of TCNQ^{·-} stacks (AABB and CCDD), where a strong exchange interaction is expected. The temperature dependence of the specific heat of a single crystal was studied in magnetic fields up to 5 T and in the temperature range from 0.4 K to 30 K. The temperature dependence of specific heat displays a broad Schottky-like maximum above 0.4 K. Using a single-ion approximation, the analysis of the temperature dependence of the specific heat below 10 K yields values for the anisotropy parameters, D/k_{B}=-1.95 K and E/k_{B}=0.3 K. These results suggest that the observed maximum in the specific heat originates from Ni⁺² ions while the exchange interaction between the transition metal ions and the TCNQ is negligible.
Keywords
EN
Year
Volume
131
Issue
4
Pages
925-927
Physical description
Dates
published
2017-04
References
  • [1] C. Draxl, D. Nabok, K. Hannewald, Acc. Chem. Res. 47, 3225 (2014), doi: 10.1021/ar500096q
  • [2] H. Fukunaga, H. Miyasaka, Angew. Chem. Int. Ed. Eng. 54, 569 (2015), doi: 10.1002/anie.201410057
  • [3] X. Zhang, M.R. Saber, A.P. Prosvirin, J.H. Reibenapies, L. Sun, M. Ballesteros-Rivas, H. Zhao, K.R. Dunbar, Inorg. Chem. Front. 2, 904 (2015), doi: 10.1039/C5QI00128E
  • [4] W. Kaim, M. Moscherosch, Coord. Chem. Rev. 129, 157 (1994), doi: 10.1016/0010-8545(94)85020-8
  • [5] H. Zhao, R.A. Heintz, K.R. Dunbar, R.D. Rogers, J. Am. Chem. Soc. 118, 12844 (1996), doi: 10.1021/ja962504w
  • [6] J.S. Miller, A.J. Epstein, Angew. Chem. Int. Ed. Eng. 33, 385 (1994), doi: 10.1002/anie.199403851
  • [7] G. Vasylets, V.A. Starodub, B. Barszcz, A. Graja, V.V. Medviediev, O.V. Shishkin, A.S. Bukrinev, Synth. Met. 191, 89 (2014), doi: 10.1016/j.synthmet.2014.02.020
  • [8] A. Radváková, D.V. Ziolkovskiy, V.O. Cheranovskii, A. Feher, M. Kajňaková, O.N. Kazheva, G.G. Alexandrov, O.A. Dyachenko, V.A. Starodub, J. Phys. Chem. Solids 70, 1471 (2009), doi: 10.1016/j.jpcs.2009.09.004
  • [9] A. Radváková, D.V. Ziolkovskiy, M. Kajňaková, B. Laskowska, B. Barszcz, A. Graja, V.A. Starodub, A. Feher, J. Phys. Condens. Matter 21, 175405 (2009), doi: 10.1088/0953-8984/21/17/175405
  • [10] J. Titiš, R. Boča, Ź. Dlháň, T. Ďurčeková, H. Fuess, R. Ivaniková, V. Mrázová, B. Papánková, I. Svoboda, Polyhedron 26, 1523 (2007), doi: 10.1016/j.poly.2006.11.054
Document Type
Publication order reference
YADDA identifier
bwmeta1.element.bwnjournal-article-appv131n4102kz
Identifiers
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.