Si₃C is predicted to take on a diamond type structure (space group: I4̅2d), at P = 1 atm, consistent with the experimental results on a cubic Si_0.75C_0.25 alloy. This structure is computed to be a semiconductor with a direct band gap of about 1.3 eV, within the desired values. Under pressure, Si₃C may transform to metastable metallic R3̅m-2 and R3̅m-3 structures at about 25 and 250 GPa, respectively. Both are layered structures with six-coordinate Si and unusual six-coordinate carbon atoms. The R3̅m-1 and R3̅m-2 structures are both estimated to be superconductors with T_c of a few Kelvin. This is the first time that superconductivity in undoped silicon carbides is calculated.

中文翻译：

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压力下潜在的半导和超导亚稳态Si ₃ C结构

的Si ₃ C被预测为采取金刚石型结构（空间群：我42 d）中，在P = 1大气压，对立方的Si的实验结果相一致_0.75 Ç _0.25合金。计算出该结构是在期望值内具有约1.3 eV的直接带隙的半导体。在压力下，硅₃ C可以以亚稳金属变换- [R 3米-2和- [R 3米-3分别结构在约25和为250GPa。两者都是具有六配位Si和不寻常的六配位碳原子的层状结构。的[R 3米-1和- [R 3米-2结构都估计以超导体Ť _Ç几个开尔文的。这是首次计算出未掺杂碳化硅中的超导性。