Showing papers by "Anvar A. Zakhidov published in 1992"
TL;DR: In this article, the effect of buckminsterfullerene (C 60 ) on the electron transfer from poly(3-alkylthiophene) to C 60 is investigated.
422 citations
TL;DR: In this paper, the magnetic properties of C60 and C70 complexes with tetrakis (dimethylamino) ethylene (TDAE) have been studied by Faraday-balance magnetization and ESR measurements.
61 citations
TL;DR: In this article, the characteristics of C60-doped poly(3-alkylthiophene) are different from the typical behavior observed in the case of conventional dopants.
Abstract: Buckminsterfullerene (C60) is effectively doped in poly(3-alkylthiophene) However, the characteristics of C60-doped poly(3-alkylthiophene) are different from the typical behavior observed in the case of conventional dopants Electrical conductivity of poly(3-alkylthiophene) increases upon C60 doping and decreases again at higher concentration of C60 Its temperature dependence is also anomalous The absorption spectrum changes markedly upon C60 doping ESR linewidth decreases from 71 G to 19 G upon C60 doping Spin density, evaluated by ESR, is enhanced upon C60 doping These doping characteristics are tentatively explained by taking electronic energy diagrams of both poly(3-alkylthiophene) and C60 into consideration
57 citations
TL;DR: In this paper, it was shown that the superconducting Tc significantly decreases in 60% 13C isotope substituted K3C60 and Rb3C 60 and the exponent α of the isotope effect, Tcrmc1/mα, is estimated roughly to be α=1.2-2.25, much higher than predicted by the BCS theory.
48 citations
TL;DR: In this article, the authors used the combined microwave spectroscopy: the nonresonant microwave absorption in lowmagnetic field (so-called LFS) together with conventional ESR for the search and study of superconductivity (SC) in the new family of fullerene molecular solids: C60, C70, C76, C78, C84 C90, and their alloys ((C60)1-y(C70)y), doped by different metals (K, Rb, In, and Ga) and iodine I2).
Abstract: We have used the combined microwave spectroscopy: the nonresonant microwave absorption in low-magnetic field (so-called LFS) together with conventional ESR for the search and study of superconductivity (SC) in the new family of fullerene molecular solids: C60, C70, C76, C78, C84 C90, and their alloys ((C60)1-y(C70)y), doped by different metals (K, Rb, In, and Ga) and iodine I2. These experiments fall into two categories: 1) Search for SC in higher fullerenes and study of the evolution of SC properties upon doping of pure (one component) fullerenes including Cm thin films. 2) Investigation of the Tc change in molecular alloys of Mx (C60)1-y(C70)y type. In the first category of experiments we discuss the evolution of LFS and ESR spectra upon variation of Rb-doping conditions: temperatures of doping: Td (C60), Td(M), and doping time td, and as a result we find the optimal conditions for vapour phase Rb-doping. Here we demonstrate that SC Tc appears and disappears with doping abruptly at a discrete v...
19 citations
TL;DR: In this article, a Raman scattering study of pristine and K doped C 60 at various doping levels by exciting in the near-IR at 1.16 eV is presented.
18 citations
TL;DR: In this article, the authors performed a Raman scattering study of superconducting thin films of A3C60 (A=K,Rb) carried out upon laser excitations at 1.16 and 2.41 eV have revealed the significant broadening and Fano-lineshapes of several low energy Hg intramolecular modes with relative intensities and widths depending on excitation energies.
Abstract: The Raman scattering study of superconducting thin films of A3C60 (A=K,Rb) carried out upon laser excitations at 1.16 and 2.41 eV have revealed the significant broadening and Fano-lineshapes of several low energy Hg intramolecular modes with relative intensities and widths depending on excitation energies. The most interesting feature of the 1.16 eV excited spectrum is the wide asymmetric band at 400 cm−1 which can be assigned by Fano-shape fitting to enormously broadened Hg(2) mode red shifted compared to its bare frequency of 408 cm−1. The narrowing of all lower Hg modes in insulating A6C60 phase indicates strong electron-phonon coupling of this Jahn-Teller modes in x=3 phase and suggests that this low energy vibrations are contributing to superconducting pairing. However the possibility to interpret the wide band at 400 cm−1 as the maximum of electronic background can not be ruled out yet and is supported by our preliminary observations of its disappearance at low temperature below Tc.
4 citations
TL;DR: In this paper, the magnetic properties of tetrakis(dimethylamino)ethylene (TDAE) have been studied based on the measurements of the Faraday-balance magnetization and the electron spin resonance (ESR).
Abstract: Magnetic properties of C60 and C70 complexes with tetrakis(dimethylamino)ethylene (TDAE) have been studied based on the measurements of the Faraday-balance magnetization and the electron spin resonance (ESR). It has been found that both TDAE-C60 and TDAE-C70 possess about one radical spin per fullerene molecule. TDAE-C60 has been confirmed to show ferromagnetic-type transition at Tc=16.7–17.5K. Appearance of a new broad and intense ESR signal below Tc of TDAE-C60 suggests that the radical spins in the magnetically ordered state rather localize on each C60 molecule and are ferromagnetically correlated. On the other hand, TDAE-C70 does not show ferromagnetism in all the temperature range down to 4.5K.
2 citations
Journal Article•
TL;DR: In this article, the combined microwave spectroscopy and conventional ESR was used for the search and study of superconductivity in the new family of fullerene molecular solids: C 60, C 70, C 78, C 84, C 90, and their alloys ((C 60 ) 1-y (C 70 ) y ), doped by different metals (K, Rb, In, and Ga) and iodine I 2
Abstract: We have used the combined microwave spectroscopy: the nonresonant microwave absorption in low-magnetic field (so-called LFS) together with conventional ESR for the search and study of superconductivity (SC) in the new family of fullerene molecular solids: C 60 , C 70 , C 78 , C 84 , C 90 , and their alloys ((C 60 ) 1-y (C 70 ) y ), doped by different metals (K, Rb, In, and Ga) and iodine I 2
1 citations