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Abstract Using first principles calculations, we show that $$\hbox {Li}_x\hbox {Al}_y\hbox {B}_{2(x+y)}$$ materials have strong electron-phonon coupling, with many having a superconducting critical temperature ( $$T_c$$ ) that exceeds that of the more familiar $$\hbox {MgB}_2$$ at ambient pressure. In particular, we find that $$\hbox {LiAlB}_4$$ is the most stable member of the family, with $$T_c > 44\,\hbox {K}$$ whilst the peak $$T_c$$ is with $$\hbox {Li}_3\hbox {AlB}_8$$ which has $$T_c > 77\,\hbox {K}$$ . Our results reveal that these materials are both thermodynamically and dynamically stable, with strong electron-phonon coupling, indicating significant potential for practical superconducting applications.

Abstract We have developed a high-throughput computational method to predict the superconducting transition temperature in stable hexagonal M $$_2$$ 2 AX phases, and applied it to all the known possible choices for M (M: Sc, Ti, V, Cr, Mn, Fe, Y, Zr, Nb, Mo, Lu, Hf and Ta). We combine this with the best candidates for A (A: Al, Cu, Ge and Sn ) and X (X: C and N) from our previous work, and predict T $$_c$$ c for 60 M $$_2$$ 2 AX-phase materials, 53 of which have never been studied before. From all of these, we identify Cr $$_2$$ 2 AlN as the best candidate for the highest T $$_c$$ c , and confirm its high T $$_c$$ c with more detailed density functional theory electron-phonon coupling calculations. Our detailed calculations predict $$T_c$$ T c = 14.8 K for Cr $$_2$$ 2 AlN, which is significantly higher than any $$T_c$$ T c value known or predicted for any material in the M $$_2$$ 2 AX family to date.

Abstract A high-throughput computational method is used to predict 39 new superconductors in the Ti-based M $$_2$$ 2 AX phases, and the best candidates are then studied in more detail using density functional theory electron–phonon coupling calculations. The detailed calculations agree with the simple predictions, and Ti $$_2$$ 2 AlX (X: B, C and N) materials are predicted to have higher values of $$T_c$$ T c than any currently known hexagonal M $$_2$$ 2 AX phases. The electronic states at the Fermi level are dominated by the Ti 3d states. The choice of X (X: B, C and N) has a significant impact on the electronic density of states but not on the phonon characteristics. The electron–phonon coupling parameter for Ti $$_2$$ 2 AlX (X: B, C and N) was determined to be 0.685, 0.743 and 0.775 with a predicted $$T_c$$ T c of 7.8 K, 10.8 K and 13.0 K, respectively.

The phrase “and so both are preserved” at the conclusion of Matthew’s version of the fasting controversy (Matt 9:14–17) with the disciples of John the Baptist is normally taken in the sense that both the new and the old wineskins are preserved, thereby confirming a sense of continuity rather than rupture with Judaism. This article argues that both the immediate syntax and the role of the image within the context of the controversy stories as a whole requires that the reference be to the new wine and the new wineskins. John’s disciples must adjust to the new way of thinking and imagining required by the kingdom. [ABSTRACT FROM AUTHOR]