title: A new tetragonal structure type for Li2B2C.
abstract: The ternary dilithium diboron carbide, Li2B2C (tetragonal, space group P-4m2, tP10), crystallizes as a new structure type and consists of structural fragments which are typical for structures of elemental lithium and boron or binary borocarbide B13C2. The symmetries of the occupied sites are .m. and 2mm. for the B and C atoms, and -4m2 and 2mm. for the Li atoms. The coordination polyhedra around the Li atoms are cuboctahedra and 15-vertex distorted pseudo-Frank-Kasper polyhedra. The environment of the B atom is a ten-vertex polyhedron. The nearest neighbours of the C atom are two B atoms, and this group is surrounded by a deformed cuboctahedron with one centred lateral facet. Electronic structure calculations using the TB-LMTO-ASA method reveal strong B...C and B...B interactions.
authors.affiliation: Department of Inorganic Chemistry, Ivan Franko Lviv National University, Kyryla and Mefodiya Street 6, 79005 Lviv, Ukraine.
authors.forename: Volodymyr
authors.initials: V
authors.lastname: Pavlyuk
authors.affiliation: Department of Inorganic Chemistry, Ivan Franko Lviv National University, Kyryla and Mefodiya Street 6, 79005 Lviv, Ukraine.
authors.forename: Viktoriya
authors.initials: V
authors.lastname: Milashys
authors.affiliation: Department of Inorganic Chemistry, Ivan Franko Lviv National University, Kyryla and Mefodiya Street 6, 79005 Lviv, Ukraine.
authors.forename: Grygoriy
authors.initials: G
authors.lastname: Dmytriv
authors.affiliation: Karlsruhe Institute of Technology (KIT), Institute for Applied Materials (IAM), Hermann-von-Helmholtz-Platz 1, D-76344 Eggenstein-Leopoldshafen, Germany.
authors.forename: Helmut
authors.initials: H
authors.lastname: Ehrenberg
keywords: Li–B–C phases; TB–LMTO–ASA method; binary borocarbide; crystal structure; dilithium diboron carbide; electron localization function (ELF) mapping; intermetallic compounds; structural materials; ternary structure