High- <mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML"><mml:msub><mml:mi>T</mml:mi><mml:mi>c</mml:mi></mml:msub></mml:math> superconductivity in doped boron-carbon clathrates

We report a high-throughput ab-initio study of the thermodynamic and superconducting proper- ties recently synthesized XB$_3$C$_3$ clathrates. These compounds, in which boron carbon form sponge-like network interconnected cages each enclosing central X atom, are attractive candidates to achieve high-Tc conventional superconductivity at ambient pressure, due simultaneous presence stiff B-C covalent tunable charge reservoir, provided by guest atom. Ternary compounds like CaB$_3$C$_3$, SrB$_3$C$_3$ BaB$_3$C$_3$ predicted exhibit T$_c$ $\lt$ 50 K moderate or pressures, may further increase up 77 if original hole-doped replacing divalent alkaline earth with monovalent alkali metal ordered $XY$B$_6$C$_6$ alloys.