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At least 1,135 records · Page 63
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DOE OSTI2020

Materials Data on Pr12Co6Pb by Materials Project

Pr12Co6Pb crystallizes in the cubic Im-3 space group. The structure is three-dimensional. Pr is bonded in a 4-coordinate geometry to three equivalent Co and one Pb atom. There are one shorter (2.83 Å) and two longer (2.97 Å) Pr–Co bond lengths. The Pr–Pb bond length is 3.70 Å. Co is bonded in a 7-coordinate geometry to six equivalent Pr and one Co atom. The Co–Co bond length is 2.26 Å. Pb is bonded in a cuboctahedral geometry to twelve equivalent Pr atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr2MgCu2 by Materials Project

MgPr2Cu2 crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. Mg is bonded to eight equivalent Pr and four equivalent Cu atoms to form a mixture of distorted corner and face-sharing MgPr8Cu4 cuboctahedra. All Mg–Pr bond lengths are 3.48 Å. All Mg–Cu bond lengths are 3.17 Å. Pr is bonded in a 6-coordinate geometry to four equivalent Mg and six equivalent Cu atoms. There are two shorter (2.99 Å) and four longer (3.05 Å) Pr–Cu bond lengths. Cu is bonded in a 9-coordinate geometry to two equivalent Mg, six equivalent Pr, and one Cu atom. The Cu–Cu bond length is 2.61 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Li2PrGa by Materials Project

Li2PrGa is Heusler structured and crystallizes in the cubic Fm-3m space group. The structure is three-dimensional. Li is bonded in a body-centered cubic geometry to four equivalent Pr and four equivalent Ga atoms. All Li–Pr bond lengths are 2.95 Å. All Li–Ga bond lengths are 2.95 Å. Pr is bonded in a distorted body-centered cubic geometry to eight equivalent Li and six equivalent Ga atoms. All Pr–Ga bond lengths are 3.41 Å. Ga is bonded in a body-centered cubic geometry to eight equivalent Li and six equivalent Pr atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr3Nb(ClO2)3 by Materials Project

Pr3Nb(O2Cl)3 crystallizes in the hexagonal P6_3/m space group. The structure is three-dimensional. Pr+3.33+ is bonded in a 10-coordinate geometry to six equivalent O2- and four equivalent Cl1- atoms. There are a spread of Pr–O bond distances ranging from 2.43–2.67 Å. There are a spread of Pr–Cl bond distances ranging from 3.02–3.09 Å. Nb5+ is bonded in a distorted pentagonal pyramidal geometry to six equivalent O2- atoms. All Nb–O bond lengths are 2.01 Å. O2- is bonded to three equivalent Pr+3.33+ and one Nb5+ atom to form a mixture of distorted edge and corner-sharing OPr3Nb tetrahedra. Cl1- is bonded in a 4-coordinate geometry to four equivalent Pr+3.33+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr2CuS2O by Materials Project

Pr2CuS2O crystallizes in the tetragonal P4/mmm space group. The structure is one-dimensional and consists of one Pr2CuS2O ribbon oriented in the (0, 0, 1) direction. Pr is bonded in a distorted linear geometry to one S and one O atom. The Pr–S bond length is 2.74 Å. The Pr–O bond length is 2.16 Å. Cu is bonded in a linear geometry to two equivalent S atoms. Both Cu–S bond lengths are 2.08 Å. S is bonded in a linear geometry to one Pr and one Cu atom. O is bonded in a linear geometry to two equivalent Pr atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr3Pd4 by Materials Project

Pd4Pr3 crystallizes in the trigonal R-3 space group. The structure is three-dimensional. Pr is bonded in a 9-coordinate geometry to nine Pd atoms. There are a spread of Pr–Pd bond distances ranging from 2.96–3.42 Å. There are three inequivalent Pd sites. In the first Pd site, Pd is bonded in a 6-coordinate geometry to six equivalent Pr atoms. In the second Pd site, Pd is bonded in a distorted octahedral geometry to six equivalent Pr atoms. In the third Pd site, Pd is bonded in a 10-coordinate geometry to seven equivalent Pr and three equivalent Pd atoms. There are one shorter (2.97 Å) and two longer (3.07 Å) Pd–Pd bond lengths.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr2InNi2 by Materials Project

Pr2Ni2In crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. Pr is bonded in a 6-coordinate geometry to six equivalent Ni and four equivalent In atoms. There are two shorter (2.94 Å) and four longer (2.97 Å) Pr–Ni bond lengths. All Pr–In bond lengths are 3.40 Å. Ni is bonded in a 9-coordinate geometry to six equivalent Pr, one Ni, and two equivalent In atoms. The Ni–Ni bond length is 2.52 Å. Both Ni–In bond lengths are 3.06 Å. In is bonded to eight equivalent Pr and four equivalent Ni atoms to form a mixture of face and corner-sharing InPr8Ni4 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr2Ni2Sn by Materials Project

Pr2Ni2Sn crystallizes in the orthorhombic Immm space group. The structure is three-dimensional. Pr is bonded in a 10-coordinate geometry to six equivalent Ni and four equivalent Sn atoms. There are two shorter (3.03 Å) and four longer (3.07 Å) Pr–Ni bond lengths. All Pr–Sn bond lengths are 3.36 Å. Ni is bonded in a 9-coordinate geometry to six equivalent Pr, one Ni, and two equivalent Sn atoms. The Ni–Ni bond length is 2.47 Å. Both Ni–Sn bond lengths are 2.75 Å. Sn is bonded to eight equivalent Pr and four equivalent Ni atoms to form a mixture of edge and face-sharing SnPr8Ni4 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrGaNi by Materials Project

PrNiGa crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Pr is bonded in a 12-coordinate geometry to six equivalent Ni and six equivalent Ga atoms. There are a spread of Pr–Ni bond distances ranging from 2.93–3.34 Å. There are a spread of Pr–Ga bond distances ranging from 3.07–3.23 Å. Ni is bonded in a 10-coordinate geometry to six equivalent Pr and four equivalent Ga atoms. There are a spread of Ni–Ga bond distances ranging from 2.54–2.71 Å. Ga is bonded in a 10-coordinate geometry to six equivalent Pr and four equivalent Ni atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr2InCu2 by Materials Project

Pr2Cu2In crystallizes in the tetragonal P4/mbm space group. The structure is three-dimensional. Pr is bonded in a 6-coordinate geometry to six equivalent Cu and four equivalent In atoms. There are two shorter (2.99 Å) and four longer (3.02 Å) Pr–Cu bond lengths. All Pr–In bond lengths are 3.47 Å. Cu is bonded in a 9-coordinate geometry to six equivalent Pr, one Cu, and two equivalent In atoms. The Cu–Cu bond length is 2.60 Å. Both Cu–In bond lengths are 3.13 Å. In is bonded to eight equivalent Pr and four equivalent Cu atoms to form a mixture of face and corner-sharing InPr8Cu4 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrDyAl4 by Materials Project

DyPrAl4 is Hexagonal Laves-derived structured and crystallizes in the cubic F-43m space group. The structure is three-dimensional. Dy is bonded in a 12-coordinate geometry to four equivalent Pr and twelve equivalent Al atoms. All Dy–Pr bond lengths are 3.46 Å. All Dy–Al bond lengths are 3.31 Å. Pr is bonded in a 12-coordinate geometry to four equivalent Dy and twelve equivalent Al atoms. All Pr–Al bond lengths are 3.31 Å. Al is bonded to three equivalent Dy, three equivalent Pr, and six equivalent Al atoms to form a mixture of edge, face, and corner-sharing AlPr3Dy3Al6 cuboctahedra. All Al–Al bond lengths are 2.82 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr3(SiNi3)2 by Materials Project

Pr3(Ni3Si)2 crystallizes in the cubic Im-3m space group. The structure is three-dimensional. Pr is bonded in a 12-coordinate geometry to eight equivalent Ni and four equivalent Si atoms. There are four shorter (2.89 Å) and four longer (2.99 Å) Pr–Ni bond lengths. All Pr–Si bond lengths are 3.18 Å. Ni is bonded in a 12-coordinate geometry to four equivalent Pr, four equivalent Ni, and two equivalent Si atoms. All Ni–Ni bond lengths are 2.58 Å. Both Ni–Si bond lengths are 2.46 Å. Si is bonded to six equivalent Pr and six equivalent Ni atoms to form a mixture of corner and face-sharing SiPr6Ni6 cuboctahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrNiSb by Materials Project

PrNiSb is hexagonal omega structure-derived structured and crystallizes in the hexagonal P-6m2 space group. The structure is three-dimensional. Pr is bonded to six equivalent Ni and six equivalent Sb atoms to form a mixture of edge and face-sharing PrNi6Sb6 cuboctahedra. All Pr–Ni bond lengths are 3.29 Å. All Pr–Sb bond lengths are 3.29 Å. Ni is bonded in a 3-coordinate geometry to six equivalent Pr and three equivalent Sb atoms. All Ni–Sb bond lengths are 2.54 Å. Sb is bonded in a 3-coordinate geometry to six equivalent Pr and three equivalent Ni atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrGa2Co3 by Materials Project

PrCo3Ga2 crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Pr is bonded in a 6-coordinate geometry to twelve equivalent Co and six equivalent Ga atoms. All Pr–Co bond lengths are 3.27 Å. All Pr–Ga bond lengths are 3.09 Å. Co is bonded to four equivalent Pr, four equivalent Co, and four equivalent Ga atoms to form a mixture of distorted corner, edge, and face-sharing CoPr4Ga4Co4 cuboctahedra. All Co–Co bond lengths are 2.68 Å. All Co–Ga bond lengths are 2.43 Å. Ga is bonded in a 9-coordinate geometry to three equivalent Pr and six equivalent Co atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrCo3Ni2 by Materials Project

PrCo3Ni2 crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Pr is bonded in a 6-coordinate geometry to twelve equivalent Co and six equivalent Ni atoms. All Pr–Co bond lengths are 3.20 Å. All Pr–Ni bond lengths are 2.87 Å. Co is bonded to four equivalent Pr, four equivalent Co, and four equivalent Ni atoms to form a mixture of edge, face, and corner-sharing CoPr4Co4Ni4 cuboctahedra. All Co–Co bond lengths are 2.49 Å. All Co–Ni bond lengths are 2.47 Å. Ni is bonded in a 12-coordinate geometry to three equivalent Pr and six equivalent Co atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PrGeIr by Materials Project

PrIrGe crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Pr is bonded in a 9-coordinate geometry to four equivalent Ir and five equivalent Ge atoms. There are a spread of Pr–Ir bond distances ranging from 3.06–3.11 Å. There are a spread of Pr–Ge bond distances ranging from 3.14–3.20 Å. Ir is bonded in a 8-coordinate geometry to four equivalent Pr and four equivalent Ge atoms. There are a spread of Ir–Ge bond distances ranging from 2.54–2.65 Å. Ge is bonded in a 10-coordinate geometry to five equivalent Pr and four equivalent Ir atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Pr14Au51 by Materials Project

Pr14Au51 crystallizes in the hexagonal P-6 space group. The structure is three-dimensional. there are five inequivalent Pr3+ sites. In the first Pr3+ site, Pr3+ is bonded in a 11-coordinate geometry to fourteen Au+0.82- atoms. There are a spread of Pr–Au bond distances ranging from 3.13–3.43 Å. In the second Pr3+ site, Pr3+ is bonded in a 8-coordinate geometry to fourteen Au+0.82- atoms. There are a spread of Pr–Au bond distances ranging from 3.13–3.38 Å. In the third Pr3+ site, Pr3+ is bonded in a 2-coordinate geometry to fourteen Au+0.82- atoms. There are a spread of Pr–Au bond distances ranging from 3.15–3.75 Å. In the fourth Pr3+ site, Pr3+ is bonded in a 1-coordinate geometry to fourteen Au+0.82- atoms. There are a spread of Pr–Au bond distances ranging from 3.01–3.42 Å. In the fifth Pr3+ site, Pr3+ is bonded in a 9-coordinate geometry to fifteen Au+0.82- atoms. There are a spread of Pr–Au bond distances ranging from 3.20–3.44 Å. There are thirteen inequivalent Au+0.82- sites. In the first Au+0.82- site, Au+0.82- is bonded in a 3-coordinate geometry to three equivalent Pr3+ and eight Au+0.82- atoms. There are two shorter (2.87 Å) and six longer (2.99 Å) Au–Au bond lengths. In the second Au+0.82- site, Au+0.82- is bonded in a 11-coordinate geometry to three equivalent Pr3+ and eight Au+0.82- atoms. There are two shorter (2.89 Å) and six longer (2.94 Å) Au–Au bond lengths. In the third Au+0.82- site, Au+0.82- is bonded in a 11-coordinate geometry to four Pr3+ and seven Au+0.82- atoms. There are a spread of Au–Au bond distances ranging from 2.85–3.16 Å. In the fourth Au+0.82- site, Au+0.82- is bonded in a 4-coordinate geometry to four Pr3+ and seven Au+0.82- atoms. There are a spread of Au–Au bond distances ranging from 2.86–3.18 Å. In the fifth Au+0.82- site, Au+0.82- is bonded to four Pr3+ and eight Au+0.82- atoms to form a mixture of edge and face-sharing AuPr4Au8 cuboctahedra. There are a spread of Au–Au bond distances ranging from 2.79–3.00 Å. In the sixth Au+0.82- site, Au+0.82- is bonded in a 12-coordinate geometry to four Pr3+ and eight Au+0.82- atoms. There are a spread of Au–Au bond distances ranging from 2.84–3.17 Å. In the seventh Au+0.82- site, Au+0.82- is bonded to four Pr3+ and eight Au+0.82- atoms to form a mixture of distorted edge and face-sharing AuPr4Au8 cuboctahedra. Both Au–Au bond lengths are 3.00 Å. In the eighth Au+0.82- site, Au+0.82- is bonded in a 12-coordinate geometry to four Pr3+ and eight Au+0.82- atoms. There are one shorter (2.83 Å) and one longer (2.93 Å) Au–Au bond lengths. In the ninth Au+0.82- site, Au+0.82- is bonded in a 11-coordinate geometry to four Pr3+ and seven Au+0.82- atoms. There are a spread of Au–Au bond distances ranging from 2.92–3.08 Å. In the tenth Au+0.82- site, Au+0.82- is bonded in a 11-coordinate geometry to four Pr3+ and seven Au+0.82- atoms. There are one shorter (2.87 Å) and one longer (2.95 Å) Au–Au bond lengths. In the eleventh Au+0.82- site, Au+0.82- is bonded in a 10-coordinate geometry to three equivalent Pr3+ and seven Au+0.82- atoms. In the twelfth Au+0.82- site, Au+0.82- is bonded in a 3-coordinate geometry to three equivalent Pr3+ and seven Au+0.82- atoms. In the thirteenth Au+0.82- site, Au+0.82- is bonded in a 3-coordinate geometry to four Pr3+ and six Au+0.82- atoms. Both Au–Au bond lengths are 2.90 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

The maximum carboxylation rate of Rubisco affects CO2 refixation in temperate broadleaved forest trees

Mesophyll resistance to CO 2 diffusion (rm) and the maximum carboxylation rate of Rubisco (Vcmax) affect photosynthetic rates, and can potentially also influence the percentage of respiratory and photorespiratory CO 2 being refixated (Pr) by mesophyll cells. Here we investigated how various leaf anatomical traits (e.g. leaf mass per area [LMA] and leaf dry matter content [LDMC]) influenced rm in leaves of mature forest trees. We further explored how rm and Vcmax in turn affected Pr, and if these traits varied among species and leaves along a light gradient. Photosynthetic CO 2 response of leaves grown in high-, medium-, and low-light environments was measured, from Pinus sylvestris [Scots pine], Picea abies [Norway spruce], Quercus robur [English oak], and Betula pendula [Silver birch] in southern Sweden. A modified version of the Farquhar-von Caemmerer-Berry model was fitted to the leaf gas exchange data to estimate Vcmax, rm and Pr. We found that of all leaf traits measured, only LMA for Q. robur was significantly higher in leaves from high-light environments. When comparing species, both rm and LMA were significantly higher in the conifers, and rm had a negative correlation with Vcmax. We found that Pr was similar between different species and functional groups, with an average of 73.2% (and SD of ±10.4) across all species. There was a strong, positive correlation between Pr and Vcmax in broadleaves, and we hypothesise that this effect might derive from a higher CO 2 drawdown near Rubisco in leaves with high Vcmax.

59 BASIC BIOLOGICAL SCIENCES↗