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4 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on IrSe2 by Materials Project

IrSe2 is Marcasite-like structured and crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are two inequivalent Ir4+ sites. In the first Ir4+ site, Ir4+ is bonded to six Se2- atoms to form a mixture of edge and corner-sharing IrSe6 octahedra. The corner-sharing octahedra tilt angles range from 56–62°. There are a spread of Ir–Se bond distances ranging from 2.45–2.54 Å. In the second Ir4+ site, Ir4+ is bonded to six Se2- atoms to form a mixture of edge and corner-sharing IrSe6 octahedra. The corner-sharing octahedra tilt angles range from 56–62°. There are a spread of Ir–Se bond distances ranging from 2.47–2.55 Å. There are four inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 3-coordinate geometry to three Ir4+ atoms. In the second Se2- site, Se2- is bonded in a 4-coordinate geometry to three equivalent Ir4+ atoms. In the third Se2- site, Se2- is bonded in a 3-coordinate geometry to three equivalent Ir4+ atoms. In the fourth Se2- site, Se2- is bonded in a distorted trigonal non-coplanar geometry to three Ir4+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on IrSe3 by Materials Project

IrSe3 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are seven inequivalent Ir5+ sites. In the first Ir5+ site, Ir5+ is bonded to six Se+1.67- atoms to form IrSe6 octahedra that share corners with four IrSe6 octahedra and corners with two equivalent IrSe5 square pyramids. The corner-sharing octahedra tilt angles range from 63–67°. There are a spread of Ir–Se bond distances ranging from 2.48–2.54 Å. In the second Ir5+ site, Ir5+ is bonded to six Se+1.67- atoms to form corner-sharing IrSe6 octahedra. The corner-sharing octahedra tilt angles range from 63–66°. There are a spread of Ir–Se bond distances ranging from 2.50–2.56 Å. In the third Ir5+ site, Ir5+ is bonded to six Se+1.67- atoms to form IrSe6 octahedra that share corners with four IrSe6 octahedra and corners with two equivalent IrSe5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 63–67°. There are a spread of Ir–Se bond distances ranging from 2.49–2.54 Å. In the fourth Ir5+ site, Ir5+ is bonded to five Se+1.67- atoms to form IrSe5 trigonal bipyramids that share corners with two equivalent IrSe6 octahedra and corners with two equivalent IrSe5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 60–63°. There are a spread of Ir–Se bond distances ranging from 2.43–2.49 Å. In the fifth Ir5+ site, Ir5+ is bonded to five Se+1.67- atoms to form corner-sharing IrSe5 trigonal bipyramids. There are a spread of Ir–Se bond distances ranging from 2.36–2.52 Å. In the sixth Ir5+ site, Ir5+ is bonded to five Se+1.67- atoms to form IrSe5 square pyramids that share corners with two equivalent IrSe6 octahedra and corners with two equivalent IrSe5 trigonal bipyramids. The corner-sharing octahedra tilt angles range from 60–63°. There are a spread of Ir–Se bond distances ranging from 2.42–2.49 Å. In the seventh Ir5+ site, Ir5+ is bonded to six Se+1.67- atoms to form corner-sharing IrSe6 octahedra. The corner-sharing octahedra tilt angles range from 63–67°. There are four shorter (2.51 Å) and two longer (2.55 Å) Ir–Se bond lengths. There are twenty-one inequivalent Se+1.67- sites. In the first Se+1.67- site, Se+1.67- is bonded in a 3-coordinate geometry to two Ir5+ and one Se+1.67- atom. The Se–Se bond length is 2.40 Å. In the second Se+1.67- site, Se+1.67- is bonded in a 2-coordinate geometry to two Ir5+ and one Se+1.67- atom. The Se–Se bond length is 2.50 Å. In the third Se+1.67- site, Se+1.67- is bonded in a 2-coordinate geometry to one Ir5+ and one Se+1.67- atom. The Se–Se bond length is 2.40 Å. In the fourth Se+1.67- site, Se+1.67- is bonded in a 2-coordinate geometry to two Ir5+ and one Se+1.67- atom. The Se–Se bond length is 2.47 Å. In the fifth Se+1.67- site, Se+1.67- is bonded in a 2-coordinate geometry to two Ir5+ and one Se+1.67- atom. The Se–Se bond length is 2.46 Å. In the sixth Se+1.67- site, Se+1.67- is bonded in a 2-coordinate geometry to two Ir5+ and one Se+1.67- atom. The Se–Se bond length is 2.48 Å. In the seventh Se+1.67- site, Se+1.67- is bonded in a 2-coordinate geometry to two Ir5+ atoms. In the eighth Se+1.67- site, Se+1.67- is bonded in a 4-coordinate geometry to three Ir5+ and one Se+1.67- atom. The Se–Se bond length is 2.53 Å. In the ninth Se+1.67- site, Se+1.67- is bonded in a 2-coordinate geometry to two Ir5+ atoms. In the tenth Se+1.67- site, Se+1.67- is bonded in a 4-coordinate geometry to three Ir5+ and one Se+1.67- atom. In the eleventh Se+1.67- site, Se+1.67- is bonded in a 2-coordinate geometry to two Ir5+ atoms. In the twelfth Se+1.67- site, Se+1.67- is bonded in a 2-coordinate geometry to two Ir5+ and one Se+1.67- atom. In the thirteenth Se+1.67- site, Se+1.67- is bonded in a 2-coordinate geometry to two Ir5+ and one Se+1.67- atom. In the fourteenth Se+1.67- site, Se+1.67- is bonded in a 2-coordinate geometry to two Ir5+ and one Se+1.67- atom. In the fifteenth Se+1.67- site, Se+1.67- is bonded in a 2-coordinate geometry to two Ir5+ atoms. In the sixteenth Se+1.67- site, Se+1.67- is bonded in a 2-coordinate geometry to one Ir5+ and one Se+1.67- atom. In the seventeenth Se+1.67- site, Se+1.67- is bonded in a 2-coordinate geometry to two Ir5+ and one Se+1.67- atom. In the eighteenth Se+1.67- site, Se+1.67- is bonded in a 3-coordinate geometry to two Ir5+ and one Se+1.67- atom. In the nineteenth Se+1.67- site, Se+1.67- is bonded in a distorted single-bond geometry to one Ir5+ atom. In the twentieth Se+1.67- site, Se+1.67- is bonded in a distorted single-bond geometry to one Ir5+ atom. In the twenty-first Se+1.67- site, Se+1.67- is bonded in a distorted single-bond geometry to one Ir5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ir3Se8 by Materials Project

Ir3Se8 crystallizes in the trigonal R-3 space group. The structure is three-dimensional. Ir+3.33+ is bonded to six Se+1.25- atoms to form corner-sharing IrSe6 octahedra. The corner-sharing octahedra tilt angles range from 63–64°. There are a spread of Ir–Se bond distances ranging from 2.51–2.53 Å. There are two inequivalent Se+1.25- sites. In the first Se+1.25- site, Se+1.25- is bonded in a 2-coordinate geometry to two equivalent Ir+3.33+ and one Se+1.25- atom. The Se–Se bond length is 2.49 Å. In the second Se+1.25- site, Se+1.25- is bonded in a 3-coordinate geometry to three equivalent Ir+3.33+ and one Se+1.25- atom. The Se–Se bond length is 2.61 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ir3Se by Materials Project

Ir3Se is alpha bismuth trifluoride structured and crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Ir sites. In the first Ir site, Ir is bonded to eight Ir and four equivalent Se atoms to form distorted IrIr8Se4 cuboctahedra that share corners with twelve equivalent IrIr8Se4 cuboctahedra, edges with eight equivalent SeIr12 cuboctahedra, edges with sixteen IrIr8Se4 cuboctahedra, faces with four equivalent SeIr12 cuboctahedra, and faces with fourteen IrIr8Se4 cuboctahedra. There are four shorter (2.76 Å) and four longer (2.85 Å) Ir–Ir bond lengths. All Ir–Se bond lengths are 2.76 Å. In the second Ir site, Ir is bonded to eight equivalent Ir and four equivalent Se atoms to form IrIr8Se4 cuboctahedra that share corners with four equivalent IrIr8Se4 cuboctahedra, corners with eight equivalent SeIr12 cuboctahedra, edges with twenty-four IrIr8Se4 cuboctahedra, faces with six equivalent SeIr12 cuboctahedra, and faces with twelve IrIr8Se4 cuboctahedra. All Ir–Se bond lengths are 2.85 Å. Se is bonded to twelve Ir atoms to form SeIr12 cuboctahedra that share corners with four equivalent SeIr12 cuboctahedra, corners with eight equivalent IrIr8Se4 cuboctahedra, edges with eight equivalent SeIr12 cuboctahedra, edges with sixteen equivalent IrIr8Se4 cuboctahedra, faces with four equivalent SeIr12 cuboctahedra, and faces with fourteen IrIr8Se4 cuboctahedra.

36 MATERIALS SCIENCE↗