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At least 307 records · Page 17
All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Materials Data on Hg2ClO6 by Materials Project

(HgO)2ClO4 crystallizes in the monoclinic P2_1/c space group. The structure is one-dimensional and consists of eight ClO4 clusters and two HgO ribbons oriented in the (1, 0, 0) direction. In each ClO4 cluster, there are four inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.45 Å. In the second O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.46 Å. In the third O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.48 Å. In the fourth O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.47 Å. Cl is bonded in a tetrahedral geometry to four O atoms. In each HgO ribbon, there are four inequivalent Hg sites. In the first Hg site, Hg is bonded in a linear geometry to two equivalent O atoms. There are one shorter (2.09 Å) and one longer (2.10 Å) Hg–O bond lengths. In the second Hg site, Hg is bonded in a distorted linear geometry to two O atoms. There are one shorter (2.09 Å) and one longer (2.10 Å) Hg–O bond lengths. In the third Hg site, Hg is bonded in a linear geometry to two O atoms. There are one shorter (2.01 Å) and one longer (2.07 Å) Hg–O bond lengths. In the fourth Hg site, Hg is bonded in a linear geometry to two O atoms. There are one shorter (2.02 Å) and one longer (2.08 Å) Hg–O bond lengths. There are four inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Hg atom. In the second O site, O is bonded in a distorted single-bond geometry to one Hg atom. In the third O site, O is bonded in a trigonal planar geometry to three Hg atoms. In the fourth O site, O is bonded in a trigonal planar geometry to three Hg atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hg5(ClO)4 by Materials Project

Hg5(OCl)4 crystallizes in the triclinic P-1 space group. The structure is two-dimensional and consists of one Hg5(OCl)4 sheet oriented in the (1, 0, 1) direction. there are three inequivalent Hg sites. In the first Hg site, Hg is bonded in a 2-coordinate geometry to two O and three Cl atoms. There are one shorter (2.12 Å) and one longer (2.17 Å) Hg–O bond lengths. There are a spread of Hg–Cl bond distances ranging from 2.80–3.02 Å. In the second Hg site, Hg is bonded in a linear geometry to two O and one Cl atom. There are one shorter (2.04 Å) and one longer (2.08 Å) Hg–O bond lengths. The Hg–Cl bond length is 3.07 Å. In the third Hg site, Hg is bonded in a linear geometry to two equivalent O atoms. Both Hg–O bond lengths are 2.07 Å. There are two inequivalent O sites. In the first O site, O is bonded in a trigonal non-coplanar geometry to three Hg atoms. In the second O site, O is bonded in a bent 120 degrees geometry to two Hg atoms. There are two inequivalent Cl sites. In the first Cl site, Cl is bonded in a 2-coordinate geometry to three Hg atoms. In the second Cl site, Cl is bonded in a distorted water-like geometry to one Hg and one Cl atom. The Cl–Cl bond length is 2.63 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hg3BI2(OF2)2 by Materials Project

Hg3(OI)2BF4 crystallizes in the monoclinic P2_1/c space group. The structure is two-dimensional and consists of four BF4 clusters and two Hg3(OI)2 sheets oriented in the (0, 1, 0) direction. In each BF4 cluster, B is bonded in a tetrahedral geometry to four F atoms. There are a spread of B–F bond distances ranging from 1.38–1.46 Å. There are four inequivalent F sites. In the first F site, F is bonded in a single-bond geometry to one B atom. In the second F site, F is bonded in a single-bond geometry to one B atom. In the third F site, F is bonded in a single-bond geometry to one B atom. In the fourth F site, F is bonded in a single-bond geometry to one B atom. In each Hg3(OI)2 sheet, there are three inequivalent Hg sites. In the first Hg site, Hg is bonded in a linear geometry to two O atoms. There are one shorter (2.03 Å) and one longer (2.06 Å) Hg–O bond lengths. In the second Hg site, Hg is bonded in a 4-coordinate geometry to two O and two I atoms. There are one shorter (2.15 Å) and one longer (2.30 Å) Hg–O bond lengths. There are one shorter (2.67 Å) and one longer (3.17 Å) Hg–I bond lengths. In the third Hg site, Hg is bonded in a 3-coordinate geometry to two O and one I atom. There are one shorter (2.18 Å) and one longer (2.37 Å) Hg–O bond lengths. The Hg–I bond length is 2.66 Å. There are two inequivalent O sites. In the first O site, O is bonded in a trigonal planar geometry to three Hg atoms. In the second O site, O is bonded in a distorted trigonal non-coplanar geometry to three Hg atoms. There are two inequivalent I sites. In the first I site, I is bonded in a single-bond geometry to one Hg atom. In the second I site, I is bonded in a distorted L-shaped geometry to two Hg atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Multiple Arabidopsis galacturonosyltransferases synthesize polymeric homogalacturonan by oligosaccharide acceptor‐dependent or de novo synthesis

SUMMARY Homogalacturonan (HG), the most abundant pectic glycan, functions as a cell wall structural and signaling molecule essential for plant growth, development and response to pathogens. HG exists as a component of pectic homoglycans, heteroglycans and glycoconjugates. HG is synthesized by members of the GALACTURONOSYLTRANSFERASE (GAUT) family. UDP‐GalA‐dependent homogalacturonan:galacturonosyltransferase (HG:GalAT) activity has previously been demonstrated for GAUTs 1, 4 and 11, as well as the GAUT1:GAUT7 complex. Here, we show that GAUTs 10, 13 and 14 are also HG:GalATs and that GAUTs 1, 10, 11, 13, 14 and 1:7 synthesize polymeric HG in vitro . Comparison of the in vitro HG:GalAT specific activities of the heterologously‐expressed proteins demonstrates GAUTs 10 and 11 with the lowest, GAUT1 and GAUT13 with moderate, and GAUT14 and the GAUT1:GAUT7 complex with the highest HG:GalAT activity. GAUT13 and GAUT14 are also shown to de novo synthesize (initiate) HG synthesis in the absence of exogenous HG acceptors, an activity previously demonstrated for GAUT1:GAUT7. The rate of de novo HG synthesis by GAUT13 and GAUT14 is similar to their acceptor dependent HG synthesis, in contrast to GAUT1:GAUT7 for which de novo synthesis occurred at much lower rates than acceptor‐dependent synthesis. The results suggest a unique role for de novo HG synthesis by GAUTs 13 and 14. The reducing end of GAUT13‐ de novo‐ synthesized HG has covalently attached UDP, indicating that UDP‐GalA serves as both a donor and acceptor substrate during de novo HG synthesis. The functional significance of unique GAUT HG:GalAT catalytic properties in the synthesis of different pectin glycan or glycoconjugate structures is discussed.

Engle, Kristen A.↗
NASA NTRS2001

Mercury Abundances and Isotopic Compositions in the Murchison (CM) and Allende (CV)Carbonaceous Chondrites

The abundance and isotopic composition of Hg was determined in bulk samples of both the Murchison (CM) and Allende (CV) carbonaceous chondrites using single- and multi-collector inductively coupled plasma mass spectrometry (ICP-MS). The bulk abundances of Hg are 294 6 15 ng/g in Murchison and 30.0 6 1.5 ng/g in Allende. These values are within the range of previous measurements of bulk Hg abundances by neutron activation analysis (NAA). Prior studies suggested that both meteorites contain isotopically anomalous Hg, with d l 96/202Hg values for the anomalous, thermal-release components from bulk samples ranging from 2260 %o to 1440 9/00 in Murchison and from 2620 9/00 to 1540 9/00 in Allende (Jovanovic and Reed, 1976a; 1976b; Kumar and Goel, 1992). Our multi-collector ICP-MS measurements suggest that the relative abundances of all seven stable Hg isotopes in both meteorites are identical to terrestrial values within 0.2 to 0.5 9/00m. On-line thermal-release experiments were performed by coupling a programmable oven with the singlecollector ICP-MS. Powdered aliquots of each meteorite were linearly heated from room temperature to 900 C over twenty-five minutes under an Ar atmosphere to measure the isotopic composition of Hg released fiom the meteorites as a h c t i o n of temperature. In separate experiments, the release profiles of S and Se were determined simultaneously with Hg to constrain the Hg distribution within the meteorites and to evaluate the possibility of Se interferences in previous NAA studies. The Hg-release patterns differ between Allende and Murchison. The Hg-release profile for Allende contains two distinct peaks, at 225" and 343"C, whereas the profile for Murchison has only one peak, at 344 C. No isotopically anomalous Hg was detected in the thermal-release experiments at a precision level of 5 to 30 9/00, depending on the isotope ratio. In both meteorites the Hg peak at ;340"C correlates with a peak in the S-release profile. This correlation suggests that Hg is associated with S-bearing phases and, thus, that HgS is a major Hg-bearing phase in both meteorites. The Hg peak at 225 C for Allende is similar to release patterns of physically adsorbed Hg on silicate and metal grains.

Lauretta, D. S.↗
DOE OSTI2020

Materials Data on Hg2ClO by Materials Project

Hg2OCl crystallizes in the monoclinic C2/c space group. The structure is three-dimensional. there are three inequivalent Hg+1.50+ sites. In the first Hg+1.50+ site, Hg+1.50+ is bonded in a 3-coordinate geometry to two equivalent O2- and two equivalent Cl1- atoms. There are one shorter (2.30 Å) and one longer (2.56 Å) Hg–O bond lengths. There are one shorter (2.61 Å) and one longer (3.31 Å) Hg–Cl bond lengths. In the second Hg+1.50+ site, Hg+1.50+ is bonded in a 2-coordinate geometry to two equivalent O2- and two equivalent Cl1- atoms. Both Hg–O bond lengths are 2.32 Å. Both Hg–Cl bond lengths are 2.89 Å. In the third Hg+1.50+ site, Hg+1.50+ is bonded in a distorted linear geometry to two equivalent O2- and four equivalent Cl1- atoms. Both Hg–O bond lengths are 2.07 Å. There are two shorter (3.25 Å) and two longer (3.40 Å) Hg–Cl bond lengths. O2- is bonded to four Hg+1.50+ atoms to form a mixture of distorted edge and corner-sharing OHg4 tetrahedra. Cl1- is bonded in a 2-coordinate geometry to five Hg+1.50+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Na8Hg3 by Materials Project

Na8Hg3 crystallizes in the trigonal R-3c space group. The structure is three-dimensional. there are four inequivalent Na sites. In the first Na site, Na is bonded to four Hg atoms to form a mixture of distorted edge and corner-sharing NaHg4 tetrahedra. There are a spread of Na–Hg bond distances ranging from 3.17–3.44 Å. In the second Na site, Na is bonded in a distorted trigonal non-coplanar geometry to three Hg atoms. There are a spread of Na–Hg bond distances ranging from 3.25–3.35 Å. In the third Na site, Na is bonded to four Hg atoms to form a mixture of distorted edge and corner-sharing NaHg4 tetrahedra. There are one shorter (3.23 Å) and three longer (3.39 Å) Na–Hg bond lengths. In the fourth Na site, Na is bonded in a 4-coordinate geometry to four Hg atoms. There are one shorter (3.25 Å) and three longer (3.34 Å) Na–Hg bond lengths. There are three inequivalent Hg sites. In the first Hg site, Hg is bonded in a distorted q6 geometry to ten Na atoms. In the second Hg site, Hg is bonded in a body-centered cubic geometry to eight Na atoms. In the third Hg site, Hg is bonded in a distorted q6 geometry to ten Na atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on SnHg6(P2Cl3)2 by Materials Project

Hg6Sn(P2Cl3)2 crystallizes in the cubic P2_13 space group. The structure is three-dimensional. there are two inequivalent Hg+1.33+ sites. In the first Hg+1.33+ site, Hg+1.33+ is bonded to two P1- and four Cl1- atoms to form distorted HgP2Cl4 octahedra that share corners with eight HgP2Cl4 octahedra, corners with two PHg3P tetrahedra, and edges with four equivalent HgP2Cl4 octahedra. The corner-sharing octahedra tilt angles range from 12–85°. Both Hg–P bond lengths are 2.50 Å. There are a spread of Hg–Cl bond distances ranging from 2.85–3.33 Å. In the second Hg+1.33+ site, Hg+1.33+ is bonded to two P1- and four Cl1- atoms to form HgP2Cl4 octahedra that share corners with eight HgP2Cl4 octahedra, corners with two PHg3P tetrahedra, and edges with four equivalent HgP2Cl4 octahedra. The corner-sharing octahedra tilt angles range from 12–85°. Both Hg–P bond lengths are 2.50 Å. There are a spread of Hg–Cl bond distances ranging from 2.93–3.35 Å. Sn2+ is bonded in a 6-coordinate geometry to six Cl1- atoms. There are three shorter (2.64 Å) and three longer (3.20 Å) Sn–Cl bond lengths. There are four inequivalent P1- sites. In the first P1- site, P1- is bonded to three equivalent Hg+1.33+ and one P1- atom to form PHg3P tetrahedra that share corners with three equivalent HgP2Cl4 octahedra and corners with three equivalent PHg3P tetrahedra. The corner-sharing octahedral tilt angles are 69°. The P–P bond length is 2.20 Å. In the second P1- site, P1- is bonded to three equivalent Hg+1.33+ and one P1- atom to form PHg3P tetrahedra that share corners with three equivalent HgP2Cl4 octahedra and corners with three equivalent PHg3P tetrahedra. The corner-sharing octahedral tilt angles are 69°. The P–P bond length is 2.21 Å. In the third P1- site, P1- is bonded to three equivalent Hg+1.33+ and one P1- atom to form PHg3P tetrahedra that share corners with three equivalent HgP2Cl4 octahedra and corners with three equivalent PHg3P tetrahedra. The corner-sharing octahedral tilt angles are 67°. In the fourth P1- site, P1- is bonded to three equivalent Hg+1.33+ and one P1- atom to form PHg3P tetrahedra that share corners with three equivalent HgP2Cl4 octahedra and corners with three equivalent PHg3P tetrahedra. The corner-sharing octahedral tilt angles are 72°. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a 5-coordinate geometry to four Hg+1.33+ and one Sn2+ atom. In the second Cl1- site, Cl1- is bonded in a 5-coordinate geometry to four Hg+1.33+ and one Sn2+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg3Hg by Materials Project

Mg3Hg crystallizes in the trigonal R32 space group. The structure is three-dimensional. there are five inequivalent Mg sites. In the first Mg site, Mg is bonded in a 3-coordinate geometry to three Hg atoms. There are a spread of Mg–Hg bond distances ranging from 2.83–3.12 Å. In the second Mg site, Mg is bonded in a distorted trigonal non-coplanar geometry to three equivalent Hg atoms. All Mg–Hg bond lengths are 2.95 Å. In the third Mg site, Mg is bonded in a 3-coordinate geometry to three Hg atoms. There are a spread of Mg–Hg bond distances ranging from 2.90–3.09 Å. In the fourth Mg site, Mg is bonded in a 3-coordinate geometry to three equivalent Hg atoms. All Mg–Hg bond lengths are 3.06 Å. In the fifth Mg site, Mg is bonded in a trigonal planar geometry to three equivalent Hg atoms. All Mg–Hg bond lengths are 2.83 Å. There are two inequivalent Hg sites. In the first Hg site, Hg is bonded in a distorted q6 geometry to ten Mg atoms. In the second Hg site, Hg is bonded in a 8-coordinate geometry to eight Mg atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hg6P4PbCl6 by Materials Project

Hg6PbP4Cl6 crystallizes in the cubic P2_13 space group. The structure is three-dimensional. there are two inequivalent Hg+1.33+ sites. In the first Hg+1.33+ site, Hg+1.33+ is bonded to two P1- and four Cl1- atoms to form HgP2Cl4 octahedra that share corners with eight HgP2Cl4 octahedra, corners with two PHg3P tetrahedra, edges with two equivalent PbCl6 octahedra, and edges with four equivalent HgP2Cl4 octahedra. The corner-sharing octahedra tilt angles range from 8–85°. Both Hg–P bond lengths are 2.50 Å. There are a spread of Hg–Cl bond distances ranging from 2.95–3.27 Å. In the second Hg+1.33+ site, Hg+1.33+ is bonded to two P1- and four Cl1- atoms to form distorted HgP2Cl4 octahedra that share corners with eight HgP2Cl4 octahedra, corners with two PHg3P tetrahedra, edges with two equivalent PbCl6 octahedra, and edges with four equivalent HgP2Cl4 octahedra. The corner-sharing octahedra tilt angles range from 8–85°. Both Hg–P bond lengths are 2.49 Å. There are a spread of Hg–Cl bond distances ranging from 2.91–3.24 Å. Pb2+ is bonded to six Cl1- atoms to form PbCl6 octahedra that share edges with twelve HgP2Cl4 octahedra. There are three shorter (2.79 Å) and three longer (3.10 Å) Pb–Cl bond lengths. There are four inequivalent P1- sites. In the first P1- site, P1- is bonded to three equivalent Hg+1.33+ and one P1- atom to form PHg3P tetrahedra that share corners with three equivalent HgP2Cl4 octahedra, corners with six ClHg4Pb square pyramids, corners with three equivalent PHg3P tetrahedra, and edges with three equivalent ClHg4Pb square pyramids. The corner-sharing octahedral tilt angles are 68°. The P–P bond length is 2.20 Å. In the second P1- site, P1- is bonded to three equivalent Hg+1.33+ and one P1- atom to form PHg3P tetrahedra that share corners with three equivalent HgP2Cl4 octahedra, corners with six ClHg4Pb square pyramids, corners with three equivalent PHg3P tetrahedra, and edges with three equivalent ClHg4Pb square pyramids. The corner-sharing octahedral tilt angles are 69°. In the third P1- site, P1- is bonded to three equivalent Hg+1.33+ and one P1- atom to form PHg3P tetrahedra that share corners with three equivalent HgP2Cl4 octahedra, corners with six ClHg4Pb square pyramids, corners with three equivalent PHg3P tetrahedra, and edges with three equivalent ClHg4Pb square pyramids. The corner-sharing octahedral tilt angles are 71°. The P–P bond length is 2.21 Å. In the fourth P1- site, P1- is bonded to three equivalent Hg+1.33+ and one P1- atom to form PHg3P tetrahedra that share corners with three equivalent HgP2Cl4 octahedra, corners with six ClHg4Pb square pyramids, corners with three equivalent PHg3P tetrahedra, and edges with three equivalent ClHg4Pb square pyramids. The corner-sharing octahedral tilt angles are 69°. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded to four Hg+1.33+ and one Pb2+ atom to form distorted ClHg4Pb square pyramids that share corners with nine ClHg4Pb square pyramids, corners with four PHg3P tetrahedra, edges with four ClHg4Pb square pyramids, and edges with two PHg3P tetrahedra. In the second Cl1- site, Cl1- is bonded to four Hg+1.33+ and one Pb2+ atom to form distorted ClHg4Pb square pyramids that share corners with nine ClHg4Pb square pyramids, corners with four PHg3P tetrahedra, edges with four ClHg4Pb square pyramids, and edges with two PHg3P tetrahedra.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hg15(As2Cl3)4 by Materials Project

Hg(Hg7(As2Cl3)2)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional and consists of two mercury molecules and one Hg7(As2Cl3)2 framework. In the Hg7(As2Cl3)2 framework, there are eight inequivalent Hg2+ sites. In the first Hg2+ site, Hg2+ is bonded to six Cl1- atoms to form edge-sharing HgCl6 octahedra. There are two shorter (2.75 Å) and four longer (2.76 Å) Hg–Cl bond lengths. In the second Hg2+ site, Hg2+ is bonded to six Cl1- atoms to form edge-sharing HgCl6 octahedra. All Hg–Cl bond lengths are 2.76 Å. In the third Hg2+ site, Hg2+ is bonded to two As+2.25- and four Cl1- atoms to form distorted HgAs2Cl4 octahedra that share corners with eight HgAs2Cl4 octahedra, corners with two AsHg3As tetrahedra, and edges with six HgCl6 octahedra. The corner-sharing octahedra tilt angles range from 16–88°. There are one shorter (2.56 Å) and one longer (2.57 Å) Hg–As bond lengths. There are a spread of Hg–Cl bond distances ranging from 3.01–3.40 Å. In the fourth Hg2+ site, Hg2+ is bonded to two As+2.25- and four Cl1- atoms to form distorted HgAs2Cl4 octahedra that share corners with eight HgAs2Cl4 octahedra, corners with two AsHg3As tetrahedra, and edges with six HgCl6 octahedra. The corner-sharing octahedra tilt angles range from 16–88°. There are one shorter (2.56 Å) and one longer (2.57 Å) Hg–As bond lengths. There are a spread of Hg–Cl bond distances ranging from 3.01–3.41 Å. In the fifth Hg2+ site, Hg2+ is bonded to two As+2.25- and four Cl1- atoms to form distorted HgAs2Cl4 octahedra that share corners with eight HgAs2Cl4 octahedra, corners with two AsHg3As tetrahedra, and edges with six HgAs2Cl4 octahedra. The corner-sharing octahedra tilt angles range from 16–88°. Both Hg–As bond lengths are 2.57 Å. There are a spread of Hg–Cl bond distances ranging from 3.01–3.41 Å. In the sixth Hg2+ site, Hg2+ is bonded to two As+2.25- and four Cl1- atoms to form distorted HgAs2Cl4 octahedra that share corners with eight HgAs2Cl4 octahedra, corners with two AsHg3As tetrahedra, and edges with six HgAs2Cl4 octahedra. The corner-sharing octahedra tilt angles range from 16–88°. Both Hg–As bond lengths are 2.56 Å. There are a spread of Hg–Cl bond distances ranging from 3.01–3.40 Å. In the seventh Hg2+ site, Hg2+ is bonded to two As+2.25- and four Cl1- atoms to form distorted HgAs2Cl4 octahedra that share corners with eight HgAs2Cl4 octahedra, corners with two AsHg3As tetrahedra, and edges with six HgCl6 octahedra. The corner-sharing octahedra tilt angles range from 16–88°. Both Hg–As bond lengths are 2.57 Å. There are a spread of Hg–Cl bond distances ranging from 3.01–3.41 Å. In the eighth Hg2+ site, Hg2+ is bonded to two As+2.25- and four Cl1- atoms to form distorted HgAs2Cl4 octahedra that share corners with eight HgAs2Cl4 octahedra, corners with two AsHg3As tetrahedra, and edges with six HgCl6 octahedra. The corner-sharing octahedra tilt angles range from 16–88°. There are one shorter (2.56 Å) and one longer (2.57 Å) Hg–As bond lengths. There are a spread of Hg–Cl bond distances ranging from 3.01–3.40 Å. There are four inequivalent As+2.25- sites. In the first As+2.25- site, As+2.25- is bonded to three Hg2+ and one As+2.25- atom to form AsHg3As tetrahedra that share corners with three HgAs2Cl4 octahedra, corners with four ClHg5 square pyramids, and corners with three AsHg3As tetrahedra. The corner-sharing octahedral tilt angles are 70°. The As–As bond length is 2.51 Å. In the second As+2.25- site, As+2.25- is bonded to three Hg2+ and one As+2.25- atom to form AsHg3As tetrahedra that share corners with three HgAs2Cl4 octahedra, corners with two ClHg5 square pyramids, corners with three AsHg3As tetrahedra, and an edgeedge with one ClHg5 square pyramid. The corner-sharing octahedral tilt angles are 74°. The As–As bond length is 2.51 Å. In the third As+2.25- site, As+2.25- is bonded to three Hg2+ and one As+2.25- atom to form AsHg3As tetrahedra that share corners with three HgAs2Cl4 octahedra, corners with four ClHg5 square pyramids, corners with three AsHg3As tetrahedra, and edges with two ClHg5 square pyramids. The corner-sharing octahedral tilt angles are 74°. In the fourth As+2.25- site, As+2.25- is bonded to three Hg2+ and one As+2.25- atom to form AsHg3As tetrahedra that share corners with three HgAs2Cl4 octahedra, corners with two ClHg5 square pyramids, corners with three AsHg3As tetrahedra, and edges with three ClHg5 square pyramids. The corner-sharing octahedral tilt angles are 70°. There are six inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a 5-coordinate geometry to five Hg2+ atoms. In the second Cl1- site, Cl1- is bonded to five Hg2+ atoms to form distorted ClHg5 square pyramids that share corners with five ClHg5 square pyramids, corners with four AsHg3As tetrahedra, and edges with two AsHg3As tetrahedra. In the third Cl1- site, Cl1- is bonded in a 5-coordinate geometry to five Hg2+ atoms. In the fourth Cl1- site, Cl1- is bonded to five Hg2+ atoms to form distorted ClHg5 square pyramids that share corners with seven ClHg5 square pyramids, corners with four AsHg3As tetrahedra, edges with two equivalent ClHg5 square pyramids, and edges with two AsHg3As tetrahedra. In the fifth Cl1- site, Cl1- is bonded to five Hg2+ atoms to form distorted ClHg5 square pyramids that share corners with seven ClHg5 square pyramids, corners with four AsHg3As tetrahedra, edges with two equivalent ClHg5 square pyramids, and edges with two AsHg3As tetrahedra. In the sixth Cl1- site, Cl1- is bonded in a 5-coordinate geometry to five Hg2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on K8Rb2Hg15(GeS4)10 by Materials Project

Rb2K8Hg15(GeS4)10 crystallizes in the triclinic P1 space group. The structure is three-dimensional. there are two inequivalent Rb1+ sites. In the first Rb1+ site, Rb1+ is bonded in a 7-coordinate geometry to eight S2- atoms. There are a spread of Rb–S bond distances ranging from 3.30–3.92 Å. In the second Rb1+ site, Rb1+ is bonded in a 7-coordinate geometry to eight S2- atoms. There are a spread of Rb–S bond distances ranging from 3.29–3.92 Å. There are eight inequivalent K1+ sites. In the first K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.28–3.53 Å. In the second K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.28–3.53 Å. In the third K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.28–3.53 Å. In the fourth K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.28–3.53 Å. In the fifth K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.28–3.53 Å. In the sixth K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.28–3.53 Å. In the seventh K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.27–3.53 Å. In the eighth K1+ site, K1+ is bonded in a 7-coordinate geometry to seven S2- atoms. There are a spread of K–S bond distances ranging from 3.28–3.53 Å. There are fifteen inequivalent Hg2+ sites. In the first Hg2+ site, Hg2+ is bonded in a see-saw-like geometry to four S2- atoms. There are two shorter (2.47 Å) and two longer (2.92 Å) Hg–S bond lengths. In the second Hg2+ site, Hg2+ is bonded in a see-saw-like geometry to four S2- atoms. There are two shorter (2.47 Å) and two longer (2.92 Å) Hg–S bond lengths. In the third Hg2+ site, Hg2+ is bonded in a see-saw-like geometry to four S2- atoms. There are two shorter (2.47 Å) and two longer (2.92 Å) Hg–S bond lengths. In the fourth Hg2+ site, Hg2+ is bonded in a see-saw-like geometry to four S2- atoms. There are two shorter (2.47 Å) and two longer (2.92 Å) Hg–S bond lengths. In the fifth Hg2+ site, Hg2+ is bonded in a see-saw-like geometry to four S2- atoms. There are two shorter (2.47 Å) and two longer (2.92 Å) Hg–S bond lengths. In the sixth Hg2+ site, Hg2+ is bonded in a see-saw-like geometry to four S2- atoms. There are two shorter (2.49 Å) and two longer (2.87 Å) Hg–S bond lengths. In the seventh Hg2+ site, Hg2+ is bonded in a see-saw-like geometry to four S2- atoms. There are a spread of Hg–S bond distances ranging from 2.49–2.87 Å. In the eighth Hg2+ site, Hg2+ is bonded in a see-saw-like geometry to four S2- atoms. There are a spread of Hg–S bond distances ranging from 2.49–2.87 Å. In the ninth Hg2+ site, Hg2+ is bonded in a see-saw-like geometry to four S2- atoms. There are two shorter (2.49 Å) and two longer (2.87 Å) Hg–S bond lengths. In the tenth Hg2+ site, Hg2+ is bonded in a see-saw-like geometry to four S2- atoms. There are two shorter (2.49 Å) and two longer (2.87 Å) Hg–S bond lengths. In the eleventh Hg2+ site, Hg2+ is bonded in a distorted linear geometry to four S2- atoms. There are a spread of Hg–S bond distances ranging from 2.38–3.31 Å. In the twelfth Hg2+ site, Hg2+ is bonded in a distorted linear geometry to four S2- atoms. There are a spread of Hg–S bond distances ranging from 2.38–3.31 Å. In the thirteenth Hg2+ site, Hg2+ is bonded in a distorted linear geometry to four S2- atoms. There are a spread of Hg–S bond distances ranging from 2.38–3.31 Å. In the fourteenth Hg2+ site, Hg2+ is bonded in a distorted linear geometry to four S2- atoms. There are two shorter (2.38 Å) and two longer (3.30 Å) Hg–S bond lengths. In the fifteenth Hg2+ site, Hg2+ is bonded in a distorted linear geometry to four S2- atoms. There are two shorter (2.38 Å) and two longer (3.30 Å) Hg–S bond lengths. There are eight inequivalent Ge4+ sites. In the first Ge4+ site, Ge4+ is bonded in a tetrahedral geometry to four S2- atoms. There are a spread of Ge–S bond distances ranging from 2.20–2.29 Å. In the second Ge4+ site, Ge4+ is bonded in a tetrahedral geometry to four S2- atoms. There are a spread of Ge–S bond distances ranging from 2.19–2.28 Å. In the third Ge4+ site, Ge4+ is bonded in a tetrahedral geometry to four S2- atoms. There are a spread of Ge–S bond distances ranging from 2.19–2.28 Å. In the fourth Ge4+ site, Ge4+ is bonded in a tetrahedral geometry to four S2- atoms. There are a spread of Ge–S bond distances ranging from 2.20–2.29 Å. In the fifth Ge4+ site, Ge4+ is bonded in a tetrahedral geometry to four S2- atoms. There are a spread of Ge–S bond distances ranging from 2.20–2.29 Å. In the sixth Ge4+ site, Ge4+ is bonded in a tetrahedral geometry to four S2- atoms. There are a spread of Ge–S bond distances ranging from 2.20–2.29 Å. In the seventh Ge4+ site, Ge4+ is bonded in a tetrahedral geometry to four S2- atoms. There are a spread of Ge–S bond distances ranging from 2.20–2.29 Å. In the eighth Ge4+ site, Ge4+ is bonded in a tetrahedral geometry to four S2- atoms. There are a spread of Ge–S bond distances ranging from 2.19–2.29 Å. There are thirty inequivalent S2- sites. In the first S2- site, S2- is bonded in a 5-coordinate geometry to two equivalent K1+, two Hg2+, and one Ge4+ atom. In the second S2- site, S2- is bonded in a 5-coordinate geometry to two equivalent K1+, two Hg2+, and one Ge4+ atom. In the third S2- site, S2- is bonded in a 5-coordinate geometry to two equivalent K1+, two Hg2+, and one Ge4+ atom. In the fourth S2- site, S2- is bonded in a 5-coordinate geometry to two equivalent K1+, two Hg2+, and one Ge4+ atom. In the fifth S2- site, S2- is bonded in a 5-coordinate geometry to one Rb1+, one K1+, two Hg2+, and one Ge4+ atom. In the sixth S2- site, S2- is bonded in a 5-coordinate geometry to two Rb1+, two Hg2+, and one Ge4+ atom. In the seventh S2- site, S2- is bonded in a 5-coordinate geometry to one Rb1+, one K1+, two Hg2+, and one Ge4+ atom. In the eighth S2- site, S2- is bonded in a 5-coordinate geometry to two K1+, two Hg2+, and one Ge4+ atom. The S–Ge bond length is 2.26 Å. In the ninth S2- site, S2- is bonded in a 4-coordinate geometry to one K1+, two Hg2+, and one Ge4+ atom. In the tenth S2- site, S2- is bonded in a 4-coordinate geometry to one Rb1+, two Hg2+, and one Ge4+ atom. In the eleventh S2- site, S2- is bonded in a 4-coordinate geometry to one Rb1+, two Hg2+, and one Ge4+ atom. In the twelfth S2- site, S2- is bonded in a 4-coordinate geometry to one K1+, two Hg2+, and one Ge4+ atom. In the thirteenth S2- site, S2- is bonded in a 1-coordinate geometry to one Rb1+, one K1+, two Hg2+, and one Ge4+ atom. In the fourteenth S2- site, S2- is bonded in a 1-coordinate geometry to one Rb1+, one K1+, two Hg2+, and one Ge4+ atom. In the fifteenth S2- site, S2- is bonded in a 4-coordinate geometry to one K1+, two Hg2+, and one Ge4+ atom. In the sixteenth S2- site, S2- is bonded in a 2-coordinate geometry to two K1+, one Hg2+, and one Ge4+ atom. In the seventeenth S2- site, S2- is bonded in a 2-coordinate geometry to two K1+, one Hg2+, and one Ge4+ atom. In the eighteenth S2- site, S2- is bonded in a 2-coordinate geometry to two K1+, one Hg2+, and one Ge4+ atom. In the nineteenth S2- site, S2- is bonded in a 2-coordinate geometry to two K1+, one Hg2+, and one Ge4+ atom. In the twentieth S2- site, S2- is bonded in a 2-coordinate geometry to two equivalent K1+, one Hg2+, and one Ge4+ atom. In the twenty-first S2- site, S2- is bonded in a 2-coordinate geometry to two equivalent Rb1+, one Hg2+, and one Ge4+ atom. In the twenty-second S2- site, S2- is bonded in a 2-coordinate geometry to two equivalent Rb1+, one Hg2+, and one Ge4+ atom. In the twenty-third S2- site, S2- is bonded in a 4-coordinate geometry to two K1+, one Hg2+, and one Ge4+ atom. In the twenty-fourth S2- site, S2- is bonded in a 4-coordinate geometry to one Rb1+, one K1+, one Hg2+, and one Ge4+ atom. In the twenty-fifth S2- site, S2- is bonded in a 4-coordinate geometry to one Rb1+, one K1+, one Hg2+, and one Ge4+ atom. In the twenty-sixth S2- site, S2- is bonded in a 4-coordinate geometry to two K1+, one Hg2+, and one Ge4+ atom. In the twenty-seventh S2- site, S2- is bonded in a 4-coordinate geometry to one Rb1+, one K1+, one Hg2+, and one Ge4+ atom. In the twenty-eighth S2- site, S2- is bonded in a 4-coordinate geometry to one Rb1+, one K1+, one Hg2+, and one Ge4+ atom. In the twenty-ninth S2- site, S2- is bonded in a 4-coordinate geometry to two K1+, one Hg2+, and one Ge4+ atom. In the thirtieth S2- site, S2- is bonded in a 4-coordinate geometry to two K1+, one Hg2+, and one Ge4+ atom. The S–Ge bond length is 2.29 Å.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on U2Hg5(AsO9)2 by Materials Project

U2Hg5(AsO9)2 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. U is bonded to seven O atoms to form distorted UO7 pentagonal bipyramids that share corners with three equivalent AsO4 tetrahedra and an edgeedge with one UO7 pentagonal bipyramid. There are a spread of U–O bond distances ranging from 1.83–2.40 Å. There are three inequivalent Hg sites. In the first Hg site, Hg is bonded in a linear geometry to two equivalent O atoms. Both Hg–O bond lengths are 2.00 Å. In the second Hg site, Hg is bonded in a distorted linear geometry to two O atoms. There are one shorter (2.04 Å) and one longer (2.05 Å) Hg–O bond lengths. In the third Hg site, Hg is bonded in a 4-coordinate geometry to four O atoms. There are a spread of Hg–O bond distances ranging from 2.10–2.66 Å. As is bonded to four O atoms to form AsO4 tetrahedra that share corners with three equivalent UO7 pentagonal bipyramids. There are a spread of As–O bond distances ranging from 1.71–1.76 Å. There are nine inequivalent O sites. In the first O site, O is bonded in a bent 150 degrees geometry to one U and one As atom. In the second O site, O is bonded in a distorted bent 150 degrees geometry to one U and one As atom. In the third O site, O is bonded in a 1-coordinate geometry to one U, one Hg, and one As atom. In the fourth O site, O is bonded in a bent 120 degrees geometry to one Hg and one As atom. In the fifth O site, O is bonded in a 2-coordinate geometry to two Hg atoms. In the sixth O site, O is bonded in a bent 120 degrees geometry to two Hg atoms. In the seventh O site, O is bonded in a trigonal planar geometry to two equivalent U and one Hg atom. In the eighth O site, O is bonded in a single-bond geometry to one U atom. In the ninth O site, O is bonded in a single-bond geometry to one U atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on InHg7S6Cl5 by Materials Project

Hg7InS6Cl5 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are eight inequivalent Hg2+ sites. In the first Hg2+ site, Hg2+ is bonded in a 2-coordinate geometry to two equivalent S2- and four Cl1- atoms. Both Hg–S bond lengths are 2.41 Å. There are two shorter (3.34 Å) and two longer (3.44 Å) Hg–Cl bond lengths. In the second Hg2+ site, Hg2+ is bonded to two S2- and four Cl1- atoms to form distorted HgS2Cl4 octahedra that share corners with two equivalent HgS3Cl3 octahedra and edges with two equivalent InS2Cl4 octahedra. The corner-sharing octahedra tilt angles range from 57–71°. There are one shorter (2.41 Å) and one longer (2.42 Å) Hg–S bond lengths. There are a spread of Hg–Cl bond distances ranging from 3.13–3.36 Å. In the third Hg2+ site, Hg2+ is bonded to three S2- and three Cl1- atoms to form distorted HgS3Cl3 octahedra that share corners with two equivalent HgS2Cl4 octahedra and corners with two equivalent InS2Cl4 octahedra. The corner-sharing octahedra tilt angles range from 34–71°. There are a spread of Hg–S bond distances ranging from 2.40–3.23 Å. There are a spread of Hg–Cl bond distances ranging from 3.00–3.35 Å. In the fourth Hg2+ site, Hg2+ is bonded in a 4-coordinate geometry to two S2- and two equivalent Cl1- atoms. Both Hg–S bond lengths are 2.41 Å. There are one shorter (3.19 Å) and one longer (3.28 Å) Hg–Cl bond lengths. In the fifth Hg2+ site, Hg2+ is bonded in a 5-coordinate geometry to three S2- and two Cl1- atoms. There are a spread of Hg–S bond distances ranging from 2.47–2.62 Å. There are one shorter (3.30 Å) and one longer (3.39 Å) Hg–Cl bond lengths. In the sixth Hg2+ site, Hg2+ is bonded in a 4-coordinate geometry to three S2- and one Cl1- atom. There are a spread of Hg–S bond distances ranging from 2.42–3.30 Å. The Hg–Cl bond length is 2.84 Å. In the seventh Hg2+ site, Hg2+ is bonded in a 5-coordinate geometry to three S2- and two Cl1- atoms. There are a spread of Hg–S bond distances ranging from 2.43–2.77 Å. There are one shorter (3.18 Å) and one longer (3.45 Å) Hg–Cl bond lengths. In the eighth Hg2+ site, Hg2+ is bonded in a distorted linear geometry to two equivalent S2- atoms. Both Hg–S bond lengths are 2.40 Å. In3+ is bonded to two S2- and four Cl1- atoms to form InS2Cl4 octahedra that share corners with two equivalent HgS3Cl3 octahedra and edges with two equivalent HgS2Cl4 octahedra. The corner-sharing octahedra tilt angles range from 34–40°. There are one shorter (2.66 Å) and one longer (2.76 Å) In–S bond lengths. There are a spread of In–Cl bond distances ranging from 2.51–2.57 Å. There are six inequivalent S2- sites. In the first S2- site, S2- is bonded in a 4-coordinate geometry to four Hg2+ atoms. In the second S2- site, S2- is bonded in a 3-coordinate geometry to three Hg2+ atoms. In the third S2- site, S2- is bonded in a 3-coordinate geometry to three Hg2+ atoms. In the fourth S2- site, S2- is bonded in a 3-coordinate geometry to four Hg2+ atoms. In the fifth S2- site, S2- is bonded in a distorted trigonal non-coplanar geometry to two Hg2+ and one In3+ atom. In the sixth S2- site, S2- is bonded in a 3-coordinate geometry to two Hg2+ and one In3+ atom. There are five inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a 1-coordinate geometry to three Hg2+ and one In3+ atom. In the second Cl1- site, Cl1- is bonded in a 1-coordinate geometry to four Hg2+ and one In3+ atom. In the third Cl1- site, Cl1- is bonded in a 1-coordinate geometry to two Hg2+ and one In3+ atom. In the fourth Cl1- site, Cl1- is bonded in a 2-coordinate geometry to four Hg2+ atoms. In the fifth Cl1- site, Cl1- is bonded in a 1-coordinate geometry to three Hg2+ and one In3+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Evaluation of engineered sorbents for the sorption of mercury from contaminated bank soils: a column study

Abstract As a global environmental pollutant, mercury (Hg) threatens our water resources and presents a substantial risk to human health. The rate and extent of immobilization of Hg 2+ (hereafter, Hg) on engineered sorbents (Thiol-SAMMS®, pine biochar, SediMite™, Organoclay™ PM-199, and quartz sand as a control) was evaluated using flow-through column experiments. The effectiveness of the sorbents was based on (1) the percentage of Hg removed in relation to the total amount of Hg passing the sorbent column, and (2) the rate of Hg uptake compared to the nonreactive tracer bromide (Br − ). All sorbents removed Hg to a certain extent, but none of the sorbents removed all the Hg introduced to the columns. Thiol-SAMMS showed the highest mean percentage of Hg removed (87% ± 2.9%), followed by Organoclay PM-199 (71% ± 0.4%), pine biochar (57% ± 22.3%), SediMite (61% ± 0.8%), and the control quartz sand (11% ± 5.6%). Thiol-SAMMS was the only sorbent to exhibit retardation of Hg in comparison to the conservative tracer Br − . For the remaining sorbents, Br − along with low concentrations of Hg were eluted within the first 3 pore volumes, indicating limited retardation of Hg. Overall, removal of Hg by sorbents was substantial, suggesting that sorbents might be suitable for deployment in contaminated environments. High concentrations of DOM leaching from the soil columns likely influenced the speciation of Hg and inhibited sorption to the sorbents. Incomplete removal of Hg by any sorbent suggests that additional optimization is needed to increase efficiency.

54 ENVIRONMENTAL SCIENCES↗
DOE OSTI2025

Evaluation of Technologies to Mitigate the Presence of Gaseous Elemental Mercury in Waste Disposal Containers

A study was conducted to evaluate sorbent technologies that can mitigate the presence of elemental mercury (Hg⁰) in waste containers for mercury-contaminated debris (MCD). Decontamination and demolition (D&D) activities at the Y-12 National Security Complex (Y-12) and other U.S. Department of Energy (DOE) Oak Ridge Reservation (ORR) facilities generate MCD requiring offsite disposal. The debris is packaged in appropriate waste containers and may be temporarily stored onsite prior to transport for treatment and/or disposal. During transportation of loads that had no visible liquid Hg at the point of origin, temperature changes can cause Hg⁰ to evaporate, condense, and form droplets on container walls. Furthermore, vibration during transportation could cause beads of Hg to be released from the debris, container walls, and ceiling, resulting in pools of liquid Hg⁰ on the container floor. Waste acceptance criteria (WAC) limitations for commercial disposal facilities, the Nevada National Security Site (NNSS), and ORR mixed low-level waste landfills prohibit the presence of any free liquids in containers identified as a solid waste form. Potential solutions to mitigate the presence of residual liquids that could be formed through vapor condensation include the use of sorbents or similar materials to capture and stabilize volatile Hg⁰ vapors and thus ensure compliance with landfill WAC requirements. This report summarizes data from small-scale laboratory experiments conducted to evaluate sorbent materials for Hg⁰ vapor suppression and sorption of liquid Hg⁰ that could form under relevant transportation and disposal conditions. A series of experiments was conducted to evaluate commercial sorbent materials and their effectiveness for Hg⁰ sorption across a temperature range from 19.4°C to 60°C. The impact of residual moisture on sorption was investigated under relevant conditions, and leaching tests were performed to assess the stability of Hg⁰ captured sorbent materials. The results provide estimates for sorbent quantities needed for a given Hg⁰ mass loading based on experimental results exposing sorbents to gaseous and liquid Hg⁰ at various mass ratios. Overall, sorbents that were most effective for Hg⁰ vapor suppression were brominated activated carbons, mackinawite-based sorbents coated on vermiculite, and sulfur-modified granular activated carbon. Elevated temperatures and moisture conditions did not result in significant increases of Hg⁰ headspace concentrations, and the materials also demonstrated high sorption capacities for the sorption of liquid Hg⁰.

12 MANAGEMENT OF RADIOACTIVE AND NON-RADIOACTIVE W↗
DOE OSTI2021

Mercury-Tolerant Ensifer medicae Strains Display High Mercuric Reductase Activity and a Protective Effect on Nitrogen Fixation in Medicago truncatula Nodules Under Mercury Stress

Mercury (Hg) is extremely toxic for all living organisms. Hg-tolerant symbiotic rhizobia have the potential to increase legume tolerance, and to our knowledge, the mechanisms underlying Hg tolerance in rhizobia have not been investigated to date. Rhizobial strains of Ensifer medicae, Rhizobium leguminosarum bv. trifolii and Bradyrhizobium canariense previously isolated from severely Hg-contaminated soils showed different levels of Hg tolerance. The ability of the strains to reduce mercury Hg 2+ to Hg o , a volatile and less toxic form of mercury, was assessed using a Hg volatilization assay. In general, tolerant strains displayed high mercuric reductase activity, which appeared to be inducible in some strains when grown at a sub-lethal HgCl 2 concentration. A strong correlation between Hg tolerance and mercuric reductase activity was observed for E. medicae strains, whereas this was not the case for the B. canariense strains, suggesting that additional Hg tolerance mechanisms could be playing a role in B. canariense. Transcript abundance from merA, the gene that encodes mercuric reductase, was quantified in tolerant and sensitive E. medicae and R. leguminosarum strains. Tolerant strains presented higher merA expression than sensitive ones, and an increase in transcript abundance was observed for some strains when bacteria were grown in the presence of a sub-lethal HgCl 2 concentration. These results suggest a regulation of mercuric reductase in rhizobia. Expression of merA genes and mercuric reductase activity were confirmed in Medicago truncatula nodules formed by a sensitive or a tolerant E. medicae strain. Transcript accumulation in nodules formed by the tolerant strain increased when Hg stress was applied, while a significant decrease in expression occurred upon stress application in nodules formed by the Hg-sensitive strain. The effect of Hg stress on nitrogen fixation was evaluated, and in our experimental conditions, nitrogenase activity was not affected in nodules formed by the tolerant strain, while a significant decrease in activity was observed in nodules elicited by the Hg-sensitive bacteria. Our results suggest that the combination of tolerant legumes with tolerant rhizobia constitutes a potentially powerful tool in the bioremediation of Hg-contaminated soils.

59 BASIC BIOLOGICAL SCIENCES↗
DOE OSTI2020

Materials Data on Ba(TlHg)2 by Materials Project

Ba(HgTl)2 crystallizes in the tetragonal P4_2/mnm space group. The structure is three-dimensional. Ba is bonded in a 12-coordinate geometry to nine Hg and six equivalent Tl atoms. There are a spread of Ba–Hg bond distances ranging from 3.67–4.03 Å. There are four shorter (3.74 Å) and two longer (4.23 Å) Ba–Tl bond lengths. There are two inequivalent Hg sites. In the first Hg site, Hg is bonded in a 2-coordinate geometry to five equivalent Ba, three Hg, and two equivalent Tl atoms. There are two shorter (2.98 Å) and one longer (2.99 Å) Hg–Hg bond lengths. Both Hg–Tl bond lengths are 3.24 Å. In the second Hg site, Hg is bonded in a 8-coordinate geometry to four equivalent Ba, two equivalent Hg, and two equivalent Tl atoms. Both Hg–Tl bond lengths are 3.18 Å. Tl is bonded in a 2-coordinate geometry to three equivalent Ba, two Hg, and five equivalent Tl atoms. There are one shorter (3.19 Å) and four longer (3.45 Å) Tl–Tl bond lengths.

36 MATERIALS SCIENCE↗