Search for high Tc in layered structures:: The case of LiB

Using electronic structure calculation we study the superconducting properties of the theoretically devised superconductor MS1-LiB (LiB). We calculate the electron-phonon coupling (lambda=0.62) and the phonon frequency logarithmic average ((log)=54.6 meV) and show that the LiB critical temperature is in the range of 10-15 K, despite the frozen-phonon deformation potential being of the same order of MgB2. As a consequence, LiB captures some of the essential physics of MgB2 but (i) the electron-phonon coupling due to sigma states is smaller and (ii) the precious contribution of the pi carriers to the critical temperature is lacking. We investigate the possible change in T-c that can be induced by doping and pressure and find that these conditions cannot easily increase T-c in LiB.