title: Novel ultra-incompressible phases of Ru2C.
abstract: The crystal structures of Ru2C were extensively investigated using the structure searching method coupled with first-principles calculations. In contrast to the previously proposed P-3m1 phase, two energetically more favorable structures with space groups P-31m and P63/mmc were found, which are stable at pressure ranges of 0-32 GPa and 32-50 GPa, respectively. The dynamical stabilities of both phases at ambient and high pressures are confirmed by the phonon dispersions. Further calculations indicate that the two new predicted phases are ultra-incompressible metals due to a strong covalent Ru-C bond.
authors: Department of Physics, SHU-Solar E R& D Lab, Shanghai University, Shanghai 200444, People's Republic of China.
authors: Jian
authors: J
authors: Lu
authors: Feng
authors: F
authors: Hong
authors: Wenjun
authors: W
authors: Lin
authors: Wei
authors: W
authors: Ren
authors: Yinwei
authors: Y
authors: Li
authors: Yanfa
authors: Y
authors: Yan