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Интеллектуальная Система Тематического Исследования НАукометрических данных |
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The fullerides with composition A2BxDyC60 (A=K,Rb,Cs; B,D=Ga,ln,Sn,Bi,Be,Al,Mg; x,y<1) have been synthesized by using liquid amalgams (alloys of metals with mercury) or with an alloy of indium and gallium (gallams) at room temperature. We assumed that Hg, Ga or heterometals can intercalate together With self-intercalated alkaline metals into the fullerite. To better deliver metal to the fullerene molecule interaction of components (fullerite C60, alkali metal and heterometal) was carried out in the organic solvent (toluene or mixture of toluene and THF in a proportion 9:1), in which fullerene is soluble. The ratio of alkali metal:fullerite was 2:1 to avoid the synthesis of the superconducting fulleride A3C60. The synthesis of the alkali metal fullerides and subsequent removal of toluene, gallium or gallam and mercury, drying of •products of reaction, and their packaging in ampoules for measurements of temperature of the superconducting transition were carried out in vacuum in the full glass facility equipment. It was found that the fulleride K2InxGayC60 is a superconductor with transition temperature Tc = 24.5 K that exceed Tc for reference K3C60 (19 K).The fulleride Rb2InxGay C60 is a superconductor with Tc = 26 K. Superconductivity of heterofulleride with a composition K2HgxC60 (x<1) was observed at temperature Tc = 22 K. Only one fulleride on the base of potassium (which does not include atoms of other alkaline metals Rb and Cs) was known before - the K2LuC60 (Tc=20 K) with T, higher than for K3C60 [1]. For the sample Rb2HgxC60, Tc= 25 K, though Rb2C60 ,as well as K2C60,are not superconductors. The fullerides with composition Rb3InxGayC60 and Cs3InxGayC60 are not superconductors and crystallized in the orthorhombic lattice. Fullerides K2GaxBiyC60; K2GaxSnyC60; (x,y<1) are superconductors.