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All sourcesNASA NTRSDOE OSTI
NASA NTRS1990

Electronic and molecular structure of carbon grains

Clusters of carbon atoms have been studied with large-scale ab initio calculations. Planar, single-sheet graphite fragments with 6 to 54 atoms were investigated, as well as the spherical C(sub 60) Buckminsterfullerene molecule. Polycyclic aromatic hydrocarbons (PAHs) have also been considered. Thermodynamic differences between diamond- and graphite-like grains have been studied in particular. Saturation of the peripheral bonds with hydrogen is found to provide a smooth and uniform convergence of the properties with increasing cluster size. For the graphite-like clusters the convergence to bulk values is much slower than for the three-dimensional complexes.

Almloef, Jan↗
DOE OSTI2020

Materials Data on Hg3H6Pt(NCl4)2 by Materials Project

PtHg3H6(NCl4)2 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. Pt2+ is bonded in a square co-planar geometry to two equivalent N3- and two equivalent Cl1- atoms. Both Pt–N bond lengths are 2.08 Å. Both Pt–Cl bond lengths are 2.32 Å. There are two inequivalent Hg2+ sites. In the first Hg2+ site, Hg2+ is bonded in a distorted linear geometry to four Cl1- atoms. There are two shorter (2.35 Å) and two longer (3.21 Å) Hg–Cl bond lengths. In the second Hg2+ site, Hg2+ is bonded in a 2-coordinate geometry to six Cl1- atoms. There are a spread of Hg–Cl bond distances ranging from 2.33–3.43 Å. N3- is bonded in a distorted trigonal non-coplanar geometry to one Pt2+ and three H1+ atoms. All N–H bond lengths are 1.03 Å. There are three inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. There are four inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a distorted single-bond geometry to two Hg2+ atoms. In the second Cl1- site, Cl1- is bonded in a distorted single-bond geometry to two equivalent Hg2+ atoms. In the third Cl1- site, Cl1- is bonded in a distorted single-bond geometry to two equivalent Hg2+ atoms. In the fourth Cl1- site, Cl1- is bonded in a 1-coordinate geometry to one Pt2+ and two Hg2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LiHo3Ge2(O4F)2 by Materials Project

LiHo3(GeO4)2F2 crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. Li1+ is bonded in a square co-planar geometry to four O2- atoms. All Li–O bond lengths are 2.12 Å. There are two inequivalent Ho3+ sites. In the first Ho3+ site, Ho3+ is bonded to six O2- and one F1- atom to form distorted HoO6F pentagonal bipyramids that share corners with two equivalent HoO6F pentagonal bipyramids, corners with four equivalent GeO4 tetrahedra, an edgeedge with one HoO6F pentagonal bipyramid, and an edgeedge with one GeO4 tetrahedra. There are a spread of Ho–O bond distances ranging from 2.29–2.44 Å. The Ho–F bond length is 2.23 Å. In the second Ho3+ site, Ho3+ is bonded in a 8-coordinate geometry to six O2- and two equivalent F1- atoms. There are a spread of Ho–O bond distances ranging from 2.29–2.56 Å. Both Ho–F bond lengths are 2.24 Å. Ge4+ is bonded to four O2- atoms to form GeO4 tetrahedra that share corners with four equivalent HoO6F pentagonal bipyramids and an edgeedge with one HoO6F pentagonal bipyramid. There are a spread of Ge–O bond distances ranging from 1.76–1.81 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to two equivalent Ho3+ and one Ge4+ atom. In the second O2- site, O2- is bonded in a 4-coordinate geometry to one Li1+, two Ho3+, and one Ge4+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to three Ho3+ and one Ge4+ atom. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to one Li1+, two Ho3+, and one Ge4+ atom. F1- is bonded in a bent 150 degrees geometry to two Ho3+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on P2PdPbO7 by Materials Project

PdPbP2O7 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Pd2+ is bonded in a square co-planar geometry to four O2- atoms. There are two shorter (2.04 Å) and two longer (2.06 Å) Pd–O bond lengths. Pb2+ is bonded to six O2- atoms to form PbO6 octahedra that share corners with six PO4 tetrahedra. There are a spread of Pb–O bond distances ranging from 2.53–2.71 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three equivalent PbO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 41–65°. There are a spread of P–O bond distances ranging from 1.50–1.62 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form PO4 tetrahedra that share corners with three equivalent PbO6 octahedra and a cornercorner with one PO4 tetrahedra. The corner-sharing octahedra tilt angles range from 10–59°. There are a spread of P–O bond distances ranging from 1.50–1.63 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to one Pb2+ and one P5+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Pd2+, one Pb2+, and one P5+ atom. In the third O2- site, O2- is bonded in a distorted single-bond geometry to one Pb2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Pd2+, one Pb2+, and one P5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Li2GePbS4 by Materials Project

Li2PbGeS4 crystallizes in the tetragonal I-42m space group. The structure is three-dimensional. Li1+ is bonded in a distorted square co-planar geometry to four equivalent S2- atoms. All Li–S bond lengths are 2.47 Å. Pb2+ is bonded in a 8-coordinate geometry to eight equivalent S2- atoms. There are four shorter (3.10 Å) and four longer (3.23 Å) Pb–S bond lengths. Ge4+ is bonded in a tetrahedral geometry to four equivalent S2- atoms. All Ge–S bond lengths are 2.24 Å. S2- is bonded in a 3-coordinate geometry to two equivalent Li1+, two equivalent Pb2+, and one Ge4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Li2EuGeS4 by Materials Project

Li2EuGeS4 crystallizes in the tetragonal I-42m space group. The structure is three-dimensional. Li1+ is bonded in a distorted square co-planar geometry to four equivalent S2- atoms. All Li–S bond lengths are 2.46 Å. Eu2+ is bonded in a 8-coordinate geometry to eight equivalent S2- atoms. There are four shorter (3.08 Å) and four longer (3.17 Å) Eu–S bond lengths. Ge4+ is bonded in a tetrahedral geometry to four equivalent S2- atoms. All Ge–S bond lengths are 2.25 Å. S2- is bonded in a 5-coordinate geometry to two equivalent Li1+, two equivalent Eu2+, and one Ge4+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LiCr3O4 by Materials Project

LiCr3O4 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. Li1+ is bonded in a square co-planar geometry to four O2- atoms. There are two shorter (2.14 Å) and two longer (2.17 Å) Li–O bond lengths. There are three inequivalent Cr+2.33+ sites. In the first Cr+2.33+ site, Cr+2.33+ is bonded to six O2- atoms to form a mixture of corner and edge-sharing CrO6 octahedra. The corner-sharing octahedra tilt angles range from 2–19°. There are a spread of Cr–O bond distances ranging from 2.09–2.47 Å. In the second Cr+2.33+ site, Cr+2.33+ is bonded to six O2- atoms to form edge-sharing CrO6 octahedra. There are a spread of Cr–O bond distances ranging from 2.04–2.13 Å. In the third Cr+2.33+ site, Cr+2.33+ is bonded to six O2- atoms to form a mixture of corner and edge-sharing CrO6 octahedra. The corner-sharing octahedra tilt angles range from 2–19°. There are a spread of Cr–O bond distances ranging from 2.09–2.48 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded to one Li1+ and four Cr+2.33+ atoms to form distorted OLiCr4 square pyramids that share corners with two equivalent OLiCr5 octahedra, corners with seven equivalent OLiCr4 square pyramids, edges with six equivalent OLiCr5 octahedra, and an edgeedge with one OLiCr4 square pyramid. The corner-sharing octahedra tilt angles range from 79–80°. In the second O2- site, O2- is bonded to one Li1+ and five Cr+2.33+ atoms to form OLiCr5 octahedra that share corners with six equivalent OLiCr5 octahedra, corners with two equivalent OLiCr4 square pyramids, edges with four equivalent OLiCr5 octahedra, and edges with six equivalent OLiCr4 square pyramids. The corner-sharing octahedral tilt angles are 0°.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SnO by Materials Project

SnO is lead oxide structured and crystallizes in the orthorhombic Pmn2_1 space group. The structure is two-dimensional and consists of one SnO sheet oriented in the (0, 0, 1) direction. Sn2+ is bonded in a distorted T-shaped geometry to three equivalent O2- atoms. There are one shorter (2.15 Å) and two longer (2.16 Å) Sn–O bond lengths. O2- is bonded in a trigonal planar geometry to three equivalent Sn2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PbO by Materials Project

PbO is TlF-II structured and crystallizes in the orthorhombic Pca2_1 space group. The structure is two-dimensional and consists of one PbO sheet oriented in the (0, 0, 1) direction. Pb2+ is bonded in a distorted T-shaped geometry to three equivalent O2- atoms. There are one shorter (2.25 Å) and two longer (2.26 Å) Pb–O bond lengths. O2- is bonded in a trigonal planar geometry to three equivalent Pb2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Cu3O2 by Materials Project

Cu3O2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. there are two inequivalent Cu+1.33+ sites. In the first Cu+1.33+ site, Cu+1.33+ is bonded in a linear geometry to two equivalent O2- atoms. Both Cu–O bond lengths are 1.84 Å. In the second Cu+1.33+ site, Cu+1.33+ is bonded in a square co-planar geometry to four equivalent O2- atoms. All Cu–O bond lengths are 2.02 Å. O2- is bonded in a square co-planar geometry to four Cu+1.33+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Ta by Materials Project

Ta crystallizes in the hexagonal P6_322 space group. The structure is three-dimensional. there are two inequivalent Ta sites. In the first Ta site, Ta is bonded in a 8-coordinate geometry to eight Ta atoms. There are a spread of Ta–Ta bond distances ranging from 2.74–2.93 Å. In the second Ta site, Ta is bonded in a distorted hexagonal planar geometry to six equivalent Ta atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KBa3(FeAs)8 by Materials Project

KBa3(FeAs)8 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. K1+ is bonded in a square co-planar geometry to four As3- atoms. There are two shorter (2.86 Å) and two longer (2.87 Å) K–As bond lengths. There are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded in a rectangular see-saw-like geometry to four As3- atoms. There are a spread of Ba–As bond distances ranging from 2.79–2.89 Å. In the second Ba2+ site, Ba2+ is bonded in a square co-planar geometry to four As3- atoms. All Ba–As bond lengths are 2.87 Å. There are four inequivalent Fe+2.12+ sites. In the first Fe+2.12+ site, Fe+2.12+ is bonded in a 4-coordinate geometry to two Fe+2.12+ and two As3- atoms. Both Fe–Fe bond lengths are 1.97 Å. There are one shorter (2.07 Å) and one longer (2.68 Å) Fe–As bond lengths. In the second Fe+2.12+ site, Fe+2.12+ is bonded in a 4-coordinate geometry to two Fe+2.12+ and two As3- atoms. There is one shorter (1.96 Å) and one longer (1.97 Å) Fe–Fe bond length. There are one shorter (2.05 Å) and one longer (2.66 Å) Fe–As bond lengths. In the third Fe+2.12+ site, Fe+2.12+ is bonded in a 4-coordinate geometry to two Fe+2.12+ and two As3- atoms. The Fe–Fe bond length is 1.96 Å. There are one shorter (2.04 Å) and one longer (2.71 Å) Fe–As bond lengths. In the fourth Fe+2.12+ site, Fe+2.12+ is bonded in a 4-coordinate geometry to two Fe+2.12+ and two As3- atoms. There are one shorter (2.04 Å) and one longer (2.71 Å) Fe–As bond lengths. There are four inequivalent As3- sites. In the first As3- site, As3- is bonded in a 4-coordinate geometry to one K1+, one Ba2+, and two Fe+2.12+ atoms. In the second As3- site, As3- is bonded in a 4-coordinate geometry to two Ba2+ and two Fe+2.12+ atoms. In the third As3- site, As3- is bonded in a 4-coordinate geometry to one K1+, one Ba2+, and two Fe+2.12+ atoms. In the fourth As3- site, As3- is bonded in a 4-coordinate geometry to two Ba2+ and two Fe+2.12+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Sr3Li by Materials Project

LiSr3 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Li is bonded in a distorted square co-planar geometry to four equivalent Sr atoms. All Li–Sr bond lengths are 3.97 Å. There are two inequivalent Sr sites. In the first Sr site, Sr is bonded in a 8-coordinate geometry to eight Sr atoms. There are four shorter (3.97 Å) and four longer (4.13 Å) Sr–Sr bond lengths. In the second Sr site, Sr is bonded to four equivalent Li and eight equivalent Sr atoms to form a mixture of edge, face, and corner-sharing SrSr8Li4 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LiSn2P3O10 by Materials Project

LiSn2P3O10 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. Li1+ is bonded in a square co-planar geometry to four O2- atoms. There are two shorter (2.07 Å) and two longer (2.09 Å) Li–O bond lengths. Sn2+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Sn–O bond distances ranging from 2.28–2.72 Å. There are three inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.52–1.60 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.52–1.66 Å. In the third P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.65 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Sn2+ and one P5+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Sn2+, and one P5+ atom. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the fourth O2- site, O2- is bonded in a single-bond geometry to two equivalent Sn2+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a 3-coordinate geometry to one Li1+, one Sn2+, and one P5+ atom. In the sixth O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the seventh O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Sn2+ and one P5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2024

Non-covalent planarizing interactions yield highly ordered and thermotropic liquid crystalline conjugated polymers

Controlling the multi-level assembly and morphological properties of conjugated polymers through structural manipulation has contributed significantly to the advancement of organic electronics. In this work, a redox active conjugated polymer, TPT–TT, composed of alternating 1,4-(2-thienyl)-2,5-dialkoxyphenylene (TPT) and thienothiophene (TT) units is reported with non-covalent intramolecular S⋯O and S⋯H–C interactions that induce controlled main-chain planarity and solid-state order. As confirmed by density functional theory (DFT) calculations, these intramolecular interactions influence the main chain conformation, promoting backbone planarization, while still allowing dihedral rotations at higher kinetic energies (higher temperature), and give rise to temperature-dependent aggregation properties. Thermotropic liquid crystalline (LC) behavior is confirmed by cross-polarized optical microscopy (CPOM) and closely correlated with multiple thermal transitions observed by differential scanning calorimetry (DSC). This LC behavior allows us to develop and utilize a thermal annealing treatment that results in thin films with notable long-range order, as shown by grazing-incidence X-ray diffraction (GIXD). Specifically, we identified a first LC phase, ranging from 218 °C to 107 °C, as a nematic phase featuring preferential face-on π–π stacking and edge-on lamellar stacking exhibiting a large extent of disorder and broad orientation distribution. A second LC phase is observed from 107 °C to 48 °C, as a smectic A phase featuring sharp, highly ordered out-of-plane lamellar stacking features and sharp tilted backbone stacking peaks, while the structure of a third LC phase with a transition at 48 °C remains unclear, but resembles that of the solid state at ambient temperature. Furthermore, the significance of thermal annealing is evident in the ∼3-fold enhancement of the electrical conductivity of ferric tosylate-doped annealed films reaching 55 S cm −1 . More importantly, thermally annealed TPT–TT films exhibit both a narrow distribution of charge-carrier mobilities (1.4 ± 0.1) × 10 −2 cm 2 V −1 s −1 along with a remarkable device yield of 100% in an organic field-effect transistor (OFET) configuration. This molecular design approach to obtain highly ordered conjugated polymers in the solid state affords a deeper understanding of how intramolecular interactions and repeat-unit symmetry impact liquid crystallinity, solution aggregation, solution to solid-state transformation, solid-state morphology, and ultimately device applications.

Chemistry↗
DOE OSTI2020

Materials Data on CuPb3(ClO2)2 by Materials Project

CuPb3(O2Cl)2 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. Cu2+ is bonded in a square co-planar geometry to four O2- atoms. All Cu–O bond lengths are 1.86 Å. There are three inequivalent Pb+2.67+ sites. In the first Pb+2.67+ site, Pb+2.67+ is bonded in a 4-coordinate geometry to four equivalent O2- and four Cl1- atoms. There are two shorter (2.31 Å) and two longer (2.33 Å) Pb–O bond lengths. There are a spread of Pb–Cl bond distances ranging from 3.33–3.42 Å. In the second Pb+2.67+ site, Pb+2.67+ is bonded in a 3-coordinate geometry to three O2- and four Cl1- atoms. There are two shorter (2.34 Å) and one longer (2.37 Å) Pb–O bond lengths. There are a spread of Pb–Cl bond distances ranging from 3.08–3.41 Å. In the third Pb+2.67+ site, Pb+2.67+ is bonded in a 3-coordinate geometry to three O2- and four Cl1- atoms. There are one shorter (2.39 Å) and two longer (2.41 Å) Pb–O bond lengths. There are a spread of Pb–Cl bond distances ranging from 3.24–3.35 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded to four Pb+2.67+ atoms to form a mixture of edge and corner-sharing OPb4 tetrahedra. In the second O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two equivalent Cu2+, one Pb+2.67+, and one Cl1- atom. The O–Cl bond length is 3.55 Å. In the third O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two equivalent Cu2+, one Pb+2.67+, and one Cl1- atom. The O–Cl bond length is 3.51 Å. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a 8-coordinate geometry to seven Pb+2.67+ and one O2- atom. In the second Cl1- site, Cl1- is bonded in a 5-coordinate geometry to five Pb+2.67+ and one O2- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on LiErO2 by Materials Project

LiErO2 crystallizes in the tetragonal I4_1/amd space group. The structure is three-dimensional. Li1+ is bonded in a distorted square co-planar geometry to four equivalent O2- atoms. All Li–O bond lengths are 2.23 Å. Er3+ is bonded to six equivalent O2- atoms to form a mixture of edge and corner-sharing ErO6 octahedra. The corner-sharing octahedral tilt angles are 16°. There are four shorter (2.23 Å) and two longer (2.30 Å) Er–O bond lengths. O2- is bonded to two equivalent Li1+ and three equivalent Er3+ atoms to form a mixture of distorted edge and corner-sharing OLi2Er3 square pyramids.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on KNa2AuO2 by Materials Project

KNa2AuO2 crystallizes in the orthorhombic Pnnm space group. The structure is three-dimensional. K1+ is bonded in a distorted square co-planar geometry to four equivalent O2- atoms. All K–O bond lengths are 2.85 Å. Na1+ is bonded in a trigonal planar geometry to three equivalent O2- atoms. There are one shorter (2.28 Å) and two longer (2.34 Å) Na–O bond lengths. Au1+ is bonded in a linear geometry to two equivalent O2- atoms. Both Au–O bond lengths are 2.04 Å. O2- is bonded to two equivalent K1+, three equivalent Na1+, and one Au1+ atom to form a mixture of distorted corner and edge-sharing OK2Na3Au octahedra. The corner-sharing octahedra tilt angles range from 0–60°.

36 MATERIALS SCIENCE↗