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HgCl2(HC2N)2(CCl)2 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of eight aziridine molecules, eight chloromethane molecules, and four mercuric chloride molecules.
Hg2TeO5 crystallizes in the orthorhombic Pna2_1 space group. The structure is three-dimensional. there are two inequivalent Hg2+ sites. In the first Hg2+ site, Hg2+ is bonded in a 2-coordinate geometry to four O2- atoms. There are a spread of Hg–O bond distances ranging from 2.10–2.86 Å. In the second Hg2+ site, Hg2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Hg–O bond distances ranging from 2.19–2.83 Å. Te6+ is bonded to six O2- atoms to form corner-sharing TeO6 octahedra. The corner-sharing octahedral tilt angles are 42°. There are a spread of Te–O bond distances ranging from 1.92–2.01 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to three Hg2+ and one Te6+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Hg2+ and one Te6+ atom. In the third O2- site, O2- is bonded in a distorted bent 150 degrees geometry to two equivalent Te6+ atoms. In the fourth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two Hg2+ and one Te6+ atom. In the fifth O2- site, O2- is bonded in a 4-coordinate geometry to three Hg2+ and one Te6+ atom.
HgBr2(HC2N)2(HBr)2 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of eight aziridine molecules, eight hydrobromic acid molecules, and four mercuric bromide molecules.
HgCl2(HC2N)2(HCl)2 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of eight aziridine molecules, eight hydrochloric acid molecules, and four mercuric chloride molecules.
Hg3ZnS2Cl4 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. there are three inequivalent Hg2+ sites. In the first Hg2+ site, Hg2+ is bonded in a rectangular see-saw-like geometry to one S2- and three Cl1- atoms. The Hg–S bond length is 2.44 Å. There are one shorter (2.54 Å) and two longer (2.86 Å) Hg–Cl bond lengths. In the second Hg2+ site, Hg2+ is bonded in a rectangular see-saw-like geometry to one S2- and three Cl1- atoms. The Hg–S bond length is 2.45 Å. There are a spread of Hg–Cl bond distances ranging from 2.54–2.88 Å. In the third Hg2+ site, Hg2+ is bonded in a rectangular see-saw-like geometry to one S2- and three Cl1- atoms. The Hg–S bond length is 2.45 Å. There are a spread of Hg–Cl bond distances ranging from 2.54–2.89 Å. Zn2+ is bonded in a tetrahedral geometry to one S2- and three Cl1- atoms. The Zn–S bond length is 2.21 Å. All Zn–Cl bond lengths are 2.39 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted rectangular see-saw-like geometry to three Hg2+ and one Cl1- atom. The S–Cl bond length is 3.61 Å. In the second S2- site, S2- is bonded in a single-bond geometry to one Zn2+ atom. There are four inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a distorted trigonal non-coplanar geometry to three Hg2+ and one S2- atom. In the second Cl1- site, Cl1- is bonded in a 1-coordinate geometry to two Hg2+ and one Zn2+ atom. In the third Cl1- site, Cl1- is bonded in a 1-coordinate geometry to two Hg2+ and one Zn2+ atom. In the fourth Cl1- site, Cl1- is bonded in a 1-coordinate geometry to two Hg2+ and one Zn2+ atom.
HgC2(NCl)2(CH3)2(CH3NH2)2 crystallizes in the monoclinic C2/c space group. The structure is zero-dimensional and consists of eight methane molecules, eight methylammonium molecules, and four HgC2(NCl)2 clusters. In each HgC2(NCl)2 cluster, Hg2+ is bonded in a 4-coordinate geometry to two equivalent C+0.67- and two equivalent Cl1- atoms. Both Hg–C bond lengths are 2.06 Å. Both Hg–Cl bond lengths are 2.95 Å. C+0.67- is bonded in a distorted linear geometry to one Hg2+ and one N3- atom. The C–N bond length is 1.17 Å. N3- is bonded in a single-bond geometry to one C+0.67- atom. Cl1- is bonded in a 2-coordinate geometry to one Hg2+ atom.
Hg2C(NCl)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are three inequivalent Hg2+ sites. In the first Hg2+ site, Hg2+ is bonded to six Cl1- atoms to form distorted HgCl6 octahedra that share corners with four equivalent HgCl6 octahedra and edges with four equivalent HgN2Cl4 octahedra. The corner-sharing octahedral tilt angles are 7°. There are a spread of Hg–Cl bond distances ranging from 2.38–3.17 Å. In the second Hg2+ site, Hg2+ is bonded in a 2-coordinate geometry to two N3- and one Cl1- atom. There are one shorter (2.09 Å) and one longer (2.13 Å) Hg–N bond lengths. The Hg–Cl bond length is 2.99 Å. In the third Hg2+ site, Hg2+ is bonded to two equivalent N3- and four equivalent Cl1- atoms to form distorted HgN2Cl4 octahedra that share corners with four equivalent HgN2Cl4 octahedra and edges with four equivalent HgCl6 octahedra. The corner-sharing octahedral tilt angles are 6°. Both Hg–N bond lengths are 2.12 Å. There are two shorter (3.01 Å) and two longer (3.22 Å) Hg–Cl bond lengths. C4+ is bonded in a linear geometry to two N3- atoms. There is one shorter (1.21 Å) and one longer (1.26 Å) C–N bond length. There are two inequivalent N3- sites. In the first N3- site, N3- is bonded in a trigonal planar geometry to two Hg2+ and one C4+ atom. In the second N3- site, N3- is bonded in a bent 120 degrees geometry to one Hg2+ and one C4+ atom. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded to five Hg2+ atoms to form a mixture of distorted corner and edge-sharing ClHg5 trigonal bipyramids. In the second Cl1- site, Cl1- is bonded in a distorted single-bond geometry to one Hg2+ atom.
Hg3(NCl3)2 crystallizes in the orthorhombic Pmna space group. The structure is three-dimensional. there are two inequivalent Hg2+ sites. In the first Hg2+ site, Hg2+ is bonded to six Cl1- atoms to form a mixture of distorted edge and corner-sharing HgCl6 octahedra. The corner-sharing octahedral tilt angles are 4°. There are a spread of Hg–Cl bond distances ranging from 2.39–3.21 Å. In the second Hg2+ site, Hg2+ is bonded in a distorted linear geometry to two equivalent N and two equivalent Cl1- atoms. Both Hg–N bond lengths are 2.15 Å. Both Hg–Cl bond lengths are 3.19 Å. N is bonded in a single-bond geometry to one Hg2+ atom. There are three inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a distorted single-bond geometry to one Hg2+ atom. In the second Cl1- site, Cl1- is bonded in a distorted L-shaped geometry to two equivalent Hg2+ atoms. In the third Cl1- site, Cl1- is bonded in a see-saw-like geometry to four Hg2+ atoms.
Geometric frustration is a key parameter controlling electronic and magnetic properties of quantum spin liquid systems, yet remains challenging to tune. Here, we coherently drive molecular vibrations with midinfrared pulses in two organic quantum spin liquid candidates, the insulating 𝜅−(BEDT−TTF) 2 Cu 2 (CN) 3 and the metallic 𝜅−(BEDT−TTF) 4 Hg 2.89 Br 8 , and probe their electronic response through ultrafast reflectivity measurements. We observe a nonlinear coupling between local molecular vibrations and nonlocal phonons, which is expected to directly modulate the geometric frustration of their triangular lattice. Furthermore, our findings establish a promising route to dynamically control frustration in nonbipartite quantum materials.
HgBr2(BrCN)2 is Cyanogen Chloride-derived structured and crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of eight cyanogen bromide molecules and four mercuric bromide molecules.
HgNBr crystallizes in the orthorhombic Pmm2 space group. The structure is two-dimensional and consists of one HgNBr sheet oriented in the (0, 0, 1) direction. Hg2+ is bonded in a bent 150 degrees geometry to two equivalent N1- atoms. Both Hg–N bond lengths are 2.12 Å. N1- is bonded in a 2-coordinate geometry to two equivalent Hg2+ and two equivalent Br1- atoms. Both N–Br bond lengths are 2.31 Å. Br1- is bonded in a distorted bent 150 degrees geometry to two equivalent N1- atoms.
Hg2Sn(SBr)2 crystallizes in the monoclinic P2_1/c space group. The structure is two-dimensional and consists of one Hg2Sn(SBr)2 sheet oriented in the (1, 0, 2) direction. there are two inequivalent Hg2+ sites. In the first Hg2+ site, Hg2+ is bonded in a distorted linear geometry to two S2- atoms. There are one shorter (2.36 Å) and one longer (2.38 Å) Hg–S bond lengths. In the second Hg2+ site, Hg2+ is bonded in a distorted linear geometry to two S2- atoms. There are one shorter (2.36 Å) and one longer (2.38 Å) Hg–S bond lengths. Sn2+ is bonded in a distorted rectangular see-saw-like geometry to one S2- and three Br1- atoms. The Sn–S bond length is 2.91 Å. There are a spread of Sn–Br bond distances ranging from 2.67–3.11 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a distorted water-like geometry to two Hg2+ atoms. In the second S2- site, S2- is bonded in a 3-coordinate geometry to two Hg2+ and one Sn2+ atom. There are two inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a single-bond geometry to one Sn2+ atom. In the second Br1- site, Br1- is bonded in a distorted L-shaped geometry to two equivalent Sn2+ atoms.
HgP2(PdO4)2 crystallizes in the orthorhombic Fddd space group. The structure is three-dimensional. Pd2+ is bonded in a square co-planar geometry to four O2- atoms. There are two shorter (2.05 Å) and two longer (2.06 Å) Pd–O bond lengths. Hg2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are four shorter (2.38 Å) and four longer (2.70 Å) Hg–O bond lengths. P5+ is bonded in a tetrahedral geometry to four O2- atoms. There is two shorter (1.55 Å) and two longer (1.57 Å) P–O bond length. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to one Pd2+, one Hg2+, and one P5+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to one Pd2+, one Hg2+, and one P5+ atom.
Hg2CdSeO6 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are two inequivalent Hg2+ sites. In the first Hg2+ site, Hg2+ is bonded in a 2-coordinate geometry to four O2- atoms. There are a spread of Hg–O bond distances ranging from 2.06–2.80 Å. In the second Hg2+ site, Hg2+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Hg–O bond distances ranging from 2.06–2.87 Å. Cd2+ is bonded to six O2- atoms to form distorted CdO6 octahedra that share corners with three equivalent SeO4 tetrahedra and an edgeedge with one CdO6 octahedra. There are a spread of Cd–O bond distances ranging from 2.33–2.46 Å. Se6+ is bonded to four O2- atoms to form SeO4 tetrahedra that share corners with three equivalent CdO6 octahedra. The corner-sharing octahedra tilt angles range from 56–64°. There are a spread of Se–O bond distances ranging from 1.65–1.70 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Cd2+ and one Se6+ atom. In the second O2- site, O2- is bonded in a distorted rectangular see-saw-like geometry to two equivalent Hg2+, one Cd2+, and one Se6+ atom. In the third O2- site, O2- is bonded to two Hg2+ and two equivalent Cd2+ atoms to form edge-sharing OCd2Hg2 tetrahedra. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to one Hg2+ and one Se6+ atom. In the fifth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to two Hg2+ and one Cd2+ atom. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to one Hg2+, one Cd2+, and one Se6+ atom.
Hg6Sn(As2Br3)2 crystallizes in the cubic P2_13 space group. The structure is three-dimensional. there are two inequivalent Hg2+ sites. In the first Hg2+ site, Hg2+ is bonded to two As+2.50- and four Br1- atoms to form HgAs2Br4 octahedra that share corners with eight HgAs2Br4 octahedra, corners with two AsHg3As tetrahedra, and edges with four equivalent HgAs2Br4 octahedra. The corner-sharing octahedra tilt angles range from 11–84°. Both Hg–As bond lengths are 2.60 Å. There are a spread of Hg–Br bond distances ranging from 3.08–3.52 Å. In the second Hg2+ site, Hg2+ is bonded to two As+2.50- and four Br1- atoms to form distorted HgAs2Br4 octahedra that share corners with eight HgAs2Br4 octahedra, corners with two AsHg3As tetrahedra, and edges with four equivalent HgAs2Br4 octahedra. The corner-sharing octahedra tilt angles range from 11–84°. Both Hg–As bond lengths are 2.61 Å. There are a spread of Hg–Br bond distances ranging from 2.98–3.53 Å. Sn4+ is bonded in a 6-coordinate geometry to six Br1- atoms. There are three shorter (2.82 Å) and three longer (3.35 Å) Sn–Br bond lengths. There are four inequivalent As+2.50- sites. In the first As+2.50- site, As+2.50- is bonded to three equivalent Hg2+ and one As+2.50- atom to form AsHg3As tetrahedra that share corners with three equivalent HgAs2Br4 octahedra and corners with three equivalent AsHg3As tetrahedra. The corner-sharing octahedral tilt angles are 68°. The As–As bond length is 2.46 Å. In the second As+2.50- site, As+2.50- is bonded to three equivalent Hg2+ and one As+2.50- atom to form AsHg3As tetrahedra that share corners with three equivalent HgAs2Br4 octahedra and corners with three equivalent AsHg3As tetrahedra. The corner-sharing octahedral tilt angles are 71°. In the third As+2.50- site, As+2.50- is bonded to three equivalent Hg2+ and one As+2.50- atom to form AsHg3As tetrahedra that share corners with three equivalent HgAs2Br4 octahedra and corners with three equivalent AsHg3As tetrahedra. The corner-sharing octahedral tilt angles are 71°. The As–As bond length is 2.46 Å. In the fourth As+2.50- site, As+2.50- is bonded to three equivalent Hg2+ and one As+2.50- atom to form AsHg3As tetrahedra that share corners with three equivalent HgAs2Br4 octahedra and corners with three equivalent AsHg3As tetrahedra. The corner-sharing octahedral tilt angles are 73°. There are two inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a 5-coordinate geometry to four Hg2+ and one Sn4+ atom. In the second Br1- site, Br1- is bonded in a 5-coordinate geometry to four Hg2+ and one Sn4+ atom.
HgZnAsHO5 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. Hg2+ is bonded in a 2-coordinate geometry to seven O2- atoms. There are a spread of Hg–O bond distances ranging from 2.17–2.74 Å. Zn2+ is bonded to six O2- atoms to form ZnO6 octahedra that share corners with four equivalent AsO4 tetrahedra and edges with two equivalent ZnO6 octahedra. There are a spread of Zn–O bond distances ranging from 2.06–2.19 Å. As5+ is bonded to four O2- atoms to form AsO4 tetrahedra that share corners with four equivalent ZnO6 octahedra. The corner-sharing octahedra tilt angles range from 48–55°. There are a spread of As–O bond distances ranging from 1.72–1.75 Å. H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a water-like geometry to one Hg2+ and one As5+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to one Hg2+, two equivalent Zn2+, and one H1+ atom. In the third O2- site, O2- is bonded in a 4-coordinate geometry to one Hg2+, two equivalent Zn2+, and one As5+ atom. In the fourth O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Hg2+, one Zn2+, and one As5+ atom.
Climate change dramatically impacts Arctic and subarctic regions, inducing shifts in wetland nutrient regimes as a consequence of thawing permafrost. Altered hydrological regimes may drive changes in the dynamics of microbial mercury (Hg) methylation and bioavailability. Important knowledge gaps remain on the contribution of specific microbial groups to methylmercury (MeHg) production in wetlands of various trophic status. Here, we measured aqueous chemistry, potential methylation rates (k meth ), volatile fatty acid (VFA) dynamics in peat-soil incubations, and genetic potential for Hg methylation across a groundwater-driven nutrient gradient in an interior Alaskan fen. We tested the hypotheses that (1) nutrient inputs will result in increased methylation potentials, and (2) syntrophic interactions contribute to methylation in subarctic wetlands. We observed that concentrations of nutrients, total Hg, and MeHg, abundance of hgcA genes, and rates of methylation in peat incubations (k meth ) were highest near the groundwater input and declined downgradient. hgcA sequences near the input were closely related to those from sulfate-reducing bacteria (SRB), methanogens, and syntrophs. Hg methylation in peat incubations collected near the input source (FPF2) were impacted by the addition of sulfate and some metabolic inhibitors while those down-gradient (FPF5) were not. Sulfate amendment to FPF2 incubations had higher k meth relative to unamended controls despite no effect on k meth from addition of the sulfate reduction inhibitor molybdate. The addition of the methanogenic inhibitor BES (25 mM) led to the accumulation of VFAs, but unlike molybdate, it did not affect Hg methylation rates. Rather, the concurrent additions of BES and molybdate significantly decreased k meth , suggesting a role for interactions between SRB and methanogens in Hg methylation. The reduction in k meth with combined addition of BES and molybdate, and accumulation of VFA in peat incubations containing BES, and a high abundance of syntroph-related hgcAsequences in peat metagenomes provide evidence for MeHg production by microorganisms growing in syntrophy. Collectively the results suggest that wetland nutrient regimes influence the activity of Hg methylating microorganisms and, consequently, Hg methylation rates. Our results provide key information about microbial Hg methylation and methylating communities under nutrient conditions that are expected to become more common as permafrost soils thaw.
Hg3(SeBr)2 crystallizes in the monoclinic C2/m space group. The structure is three-dimensional. there are five inequivalent Hg2+ sites. In the first Hg2+ site, Hg2+ is bonded to two Se2- and three Br1- atoms to form distorted HgSe2Br3 square pyramids that share corners with two HgSe2Br4 octahedra, a cornercorner with one HgSe2Br3 square pyramid, edges with two HgSe2Br4 octahedra, and an edgeedge with one HgSe2Br3 square pyramid. The corner-sharing octahedra tilt angles range from 59–61°. Both Hg–Se bond lengths are 2.59 Å. There are a spread of Hg–Br bond distances ranging from 2.93–3.52 Å. In the second Hg2+ site, Hg2+ is bonded to two equivalent Se2- and four Br1- atoms to form HgSe2Br4 octahedra that share corners with four equivalent HgSe2Br4 octahedra, corners with two equivalent HgSe2Br3 square pyramids, edges with four HgSe2Br4 octahedra, and edges with two equivalent HgSe2Br3 square pyramids. The corner-sharing octahedra tilt angles range from 4–9°. Both Hg–Se bond lengths are 2.56 Å. There are two shorter (3.33 Å) and two longer (3.35 Å) Hg–Br bond lengths. In the third Hg2+ site, Hg2+ is bonded to two equivalent Se2- and four Br1- atoms to form HgSe2Br4 octahedra that share corners with four equivalent HgSe2Br4 octahedra, corners with two equivalent HgSe2Br3 square pyramids, edges with four HgSe2Br4 octahedra, and edges with two equivalent HgSe2Br3 square pyramids. The corner-sharing octahedra tilt angles range from 4–9°. Both Hg–Se bond lengths are 2.56 Å. There are two shorter (3.25 Å) and two longer (3.42 Å) Hg–Br bond lengths. In the fourth Hg2+ site, Hg2+ is bonded in a 5-coordinate geometry to two equivalent Se2- and three Br1- atoms. Both Hg–Se bond lengths are 2.55 Å. There are a spread of Hg–Br bond distances ranging from 3.12–3.39 Å. In the fifth Hg2+ site, Hg2+ is bonded in a 4-coordinate geometry to two equivalent Se2- and three Br1- atoms. Both Hg–Se bond lengths are 2.56 Å. There are a spread of Hg–Br bond distances ranging from 3.01–3.66 Å. There are two inequivalent Se2- sites. In the first Se2- site, Se2- is bonded in a 3-coordinate geometry to three Hg2+ atoms. In the second Se2- site, Se2- is bonded in a 3-coordinate geometry to three Hg2+ atoms. There are four inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a 5-coordinate geometry to five Hg2+ atoms. In the second Br1- site, Br1- is bonded in a 4-coordinate geometry to seven Hg2+ atoms. In the third Br1- site, Br1- is bonded in a 3-coordinate geometry to three Hg2+ atoms. In the fourth Br1- site, Br1- is bonded in a 5-coordinate geometry to five Hg2+ atoms.