Using first principles calculations, we show that [Formula: see text] materials have strong electron-phonon coupling, with many having a superconducting critical temperature ([Formula: see text]) that exceeds that of the more familiar [Formula: see text] at ambient pressure. In particular, we find that [Formula: see text] is the most stable member of the family, with [Formula: see text] whilst the peak [Formula: see text] is with [Formula: see text] which has [Formula: see text]. Our results reveal that these materials are both thermodynamically and dynamically stable, with strong electron-phonon coupling, indicating significant potential for practical superconducting applications.
View Article and Find Full Text PDFWe have developed a high-throughput computational method to predict the superconducting transition temperature in stable hexagonal M[Formula: see text]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[Formula: see text] for 60 M[Formula: see text]AX-phase materials, 53 of which have never been studied before. From all of these, we identify Cr[Formula: see text]AlN as the best candidate for the highest T[Formula: see text], and confirm its high T[Formula: see text] with more detailed density functional theory electron-phonon coupling calculations.
View Article and Find Full Text PDFA high-throughput computational method is used to predict 39 new superconductors in the Ti-based M[Formula: see text]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[Formula: see text]AlX (X: B, C and N) materials are predicted to have higher values of [Formula: see text] than any currently known hexagonal M[Formula: see text]AX phases. The electronic states at the Fermi level are dominated by the Ti 3d states.
View Article and Find Full Text PDFPrevious first-principles calculations have failed to reproduce many of the key thermoelectric features of FeVAl, e.g. the maximum values of the Seebeck coefficient S and its asymmetry with respect to the chemical potential.
View Article and Find Full Text PDFOrganic molecular crystals contain long-range dispersion interactions that can be challenging for solid-state methods such as density functional theory (DFT) to capture, and in some industrial sectors are overlooked in favor of classical methods to calculate atomistic properties. Hence, this publication addresses the critical question of whether dispersion corrected DFT calculations for organic crystals can reproduce the structural and energetic trends seen from experiment, i.e.
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