We employ the chemical fragment formalism to perform a targeted superconductor search in the Nb-Ru-B system, yielding the orthorhombic metal-rich boride NbRuB, which displays BCS-like superconductivity with a Tc = 3.1 K. NbRuB is derived from the chemical fragments Nb3B2 + Ru3B, in which the Nb3B2 fragment contains B-B dimers and the Ru3B fragment contains isolated B atoms. A charge transfer occurs between the fragments. The results indicate that the fragment formalism is a useful chemical tool for the design of new intermetallic superconductors much the same way as the charge reservoir concept has been a useful chemical tool for the design of new copper oxide superconductors.
@article{arxiv.1502.06981,
title = {Superconducting NbRuB derived through the fragment formalism},
author = {Weiwei Xie and Huixia Luo and K. Baroudi and J. W. Krizan and B. F. Phelan and R. J. Cava},
journal= {arXiv preprint arXiv:1502.06981},
year = {2015}
}