Electronic structure, phase stability, and hardness of the osmium borides, carbides, nitrides, and oxides: First-principles calculations

A New Potential Superhard Phase of OsN_2

“…For P nnm phase, the calculated lattice parameters are in good agreement with the reported experimental and theoretical values [8,9,31,32], and larger deviations from the experimental lattice parameters are found in both a (0.82%) and b (0.58%) directions, respectively, but smaller deviation from the experimental lattice parameters is found in c (0.71%) direction. For F m-3m phase, the calculated lattice parameters are also in good agreement with the reported calculated results [7,12,33,34].…”

“…[34]; h Ref. [33] phases are very close, but the P nnm OsN 2 has a slightly lower value. Our results suggest that C2/m phase is a metastable state for OsN 2 and the F m-3m phase is relatively dicult to be directly synthesized.…”

Mechanical and electronic properties of diborides of transition 3d–5d metals from first principles: Toward search of novel ultra-incompressible and superhard materials

“…Besides intensive experimental studies and semi-empirical estimations, extensive efforts [51,106,135,136,269,282,283,[301][302][303][308][309][310][311][312][313][314][315][316][317][318][319][320][321] were made recently in ab initio prediction and [283]. c Ref.…”

Predicting new superhard phases

“…However, the true crystal structure of cBC 2 N still remains debatable. For the compounds formed by heavy transition metals and light elements, a variety of structure types within the substitutional methodology were considered to design new superhard materials, including the zinc-blende, rock salt, pyrite, rutile, fluorite, WC, CaCl 2 , MoC 2 , and CoSb 2 types [61][62][63][64][65][66][67][68][69][70][71][72]. The theoretical results demonstrated that these compounds possess ultrahigh bulk modulus (ultraincompressibility).…”