Endohedral Ga clusters filled with Mo are building units of homologous Mo_(8)Ga_(41),Mo_(6)Ga_(31),and Mo_(4)Ga_(21)-based compounds–a rich family of strongly coupled superconductors showing hints of multigap superco...Endohedral Ga clusters filled with Mo are building units of homologous Mo_(8)Ga_(41),Mo_(6)Ga_(31),and Mo_(4)Ga_(21)-based compounds–a rich family of strongly coupled superconductors showing hints of multigap superconductivity.The crystal structures of Mo_(8)Ga_(41),Mo_(6)Ga_(31),and Mo_(4)Ga_(21)can be derived from the simple cubic lattice of PtHg4-type MoGa_(4).Here,we construct the superconducting Mo_(4)Ga_(21)structure type starting from the electron-precise MoGa_(4)cubic framework and report the electronic structures of MoGa_(4),Mo_(4)Ga_(21),Mo_(4)Ga_(20)Sb,and Mo_(4)Ga_(20)Te.The valence electron count of 18 e−per Mo atom,which defines the optimum band filling in MoGa_(4),separates the bonding and antibonding Mo–Ga interactions within the Mo_(4)Ga_(21)structure type.Total energy calculations reveal that Mo_(4)Ga_(20)Sb and Mo_(4)Ga_(20)Te superconductors with critical temperatures of Tc=6.6 K and 4.6 K,respectively,are favorable in energy with respect to the parent MoGa_(4)cubic framework,where semiconducting properties are expected.展开更多
基金supported by the Russian Science Foundation(grant no.19-73-00042)the financial support provided by the European Regional Development Fund and the program Mobilitas Pluss(grant no.MOBJD449)the financial support by the Federal Ministry for Education and Research under the Sofja Kovalevskaya Award of the Alexander von Humboldt Foundation.
文摘Endohedral Ga clusters filled with Mo are building units of homologous Mo_(8)Ga_(41),Mo_(6)Ga_(31),and Mo_(4)Ga_(21)-based compounds–a rich family of strongly coupled superconductors showing hints of multigap superconductivity.The crystal structures of Mo_(8)Ga_(41),Mo_(6)Ga_(31),and Mo_(4)Ga_(21)can be derived from the simple cubic lattice of PtHg4-type MoGa_(4).Here,we construct the superconducting Mo_(4)Ga_(21)structure type starting from the electron-precise MoGa_(4)cubic framework and report the electronic structures of MoGa_(4),Mo_(4)Ga_(21),Mo_(4)Ga_(20)Sb,and Mo_(4)Ga_(20)Te.The valence electron count of 18 e−per Mo atom,which defines the optimum band filling in MoGa_(4),separates the bonding and antibonding Mo–Ga interactions within the Mo_(4)Ga_(21)structure type.Total energy calculations reveal that Mo_(4)Ga_(20)Sb and Mo_(4)Ga_(20)Te superconductors with critical temperatures of Tc=6.6 K and 4.6 K,respectively,are favorable in energy with respect to the parent MoGa_(4)cubic framework,where semiconducting properties are expected.
