Analogy with alkali-doped fulleranes suggests the advent of high-$T_c$ superconductivity in Li-doped α-rhombohedral (R) boron. The difficulty in preparation of doped α-R boron hindered the potential of superconductivity. Recently, by improving the preparation method, doping of Li to α-R has been successful, showing superconductivity. Unfortunately, the $T_c$ is not so high as expected, namely, around 5 K for a Li content of 2.5 at.% (B₁₂Li_0.3). Band calculations show that the DOS at the Fermi level increases as the Li concentration is increased, reaching the maximum at the Li content 7.7 at.% (B₁₂Li), where the highest $T_c$ is predicted. A practical problem is the difficulty of doping with such high concentrations. An idea of use of Li-doped β-R boron with the aid of a high-pressure technique has been proposed. High concentrations were already achieved for β-R boron up to the Li content 15 at.% (B₁₀₅Li₁₈), although these samples were nonmetal. The recently established phase diagram of boron shows that β-R boron is transformed to α-R boron at high pressures. From this, it may be possible that, starting from Li-doped β-R boron, subjecting it to high pressure, we will have a transition to Li-doped α-R boron. This paper presents a theoretical study to examine the possibility of this transformation. It is found that Li-doped β-R boron is an alloy system, while it has two stoichiometric compounds with the compositions B₁₀₄Li₈ and B₁₀₄Li₁₆. These compounds are stable semiconductors at ambient pressure, where hardening takes place on heavily doping. The transformation from β-R B₁₀₄Li₈ to α-R B₁₂Li will occur at $p>72$ GPa, provided that a path to further high-concentration compound B₁₀₄Li₁₆ is avoided by some means.

与碱掺杂的富勒烯类似，表明高-${Ť}_C$掺锂的α-菱形（R）硼的超导性。制备掺杂的α- R硼的困难阻碍了超导的潜力。最近，通过改进制备方法，已经成功地将Li掺杂到α- R中，显示出超导性。不幸的是，${Ť}_C$Li的含量不如预期的高，即，对于2.5at。％的Li含量（B ₁₂ Li _0.3）而言约为5K 。能带计算表明，随着Li浓度的增加，费米能级的DOS增加，在Li含量为7.7 at。％（B ₁₂ Li）时达到最大值，最高${Ť}_C$被预测。一个实际的问题是难以掺杂如此高的浓度。已经提出了借助于高压技术使用掺锂的β - R硼的想法。尽管这些样品是非金属的，但β- R硼的高浓度已达到Li含量15 at。％（B ₁₀₅ Li ₁₈）。最近建立的硼相图表明，β - R硼在高压下转变为α- R硼。由此看来，从掺锂的β - R硼开始，使其处于高压状态，我们可能会过渡到掺锂的α-R硼。本文提出了一项理论研究，以检验这种转变的可能性。发现掺Li的β - R硼是合金体系，同时它具有两种化学计量的化合物，其组成为B ₁₀₄ Li ₈和B ₁₀₄ Li ₁₆。这些化合物在环境压力下是稳定的半导体，在重掺杂下会发生硬化。从β- RB ₁₀₄ Li ₈到α- RB ₁₂ Li的转变将在$p>72$GPa，条件是通过某种方式避免了进一步的高浓度化合物B ₁₀₄ Li _16的生成。