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A bis(yldiide) mercury complex [Hg{C(PPh 3 )(SPPh 2 )} 2 ] has been isolated and used as a mild transmetalation reagent to form the first substituted actinide yldiide complexes, which exhibit highly polar metal carbon interactions.
Cs5Hg19 crystallizes in the tetragonal I4/m space group. The structure is three-dimensional. there are two inequivalent Cs sites. In the first Cs site, Cs is bonded in a 2-coordinate geometry to seventeen Hg atoms. There are a spread of Cs–Hg bond distances ranging from 3.88–4.39 Å. In the second Cs site, Cs is bonded in a 8-coordinate geometry to sixteen Hg atoms. There are eight shorter (3.98 Å) and eight longer (4.27 Å) Cs–Hg bond lengths. There are four inequivalent Hg sites. In the first Hg site, Hg is bonded in a 10-coordinate geometry to five Cs and five Hg atoms. There are a spread of Hg–Hg bond distances ranging from 3.16–3.29 Å. In the second Hg site, Hg is bonded in a 8-coordinate geometry to four equivalent Cs and four equivalent Hg atoms. In the third Hg site, Hg is bonded in a 10-coordinate geometry to four Cs and six Hg atoms. There are two shorter (3.36 Å) and one longer (3.42 Å) Hg–Hg bond lengths. In the fourth Hg site, Hg is bonded in a distorted cuboctahedral geometry to four equivalent Cs and eight equivalent Hg atoms.
This report presents revisions to the methodology for estimating the utility sector impacts associated with electricity demand reductions, first published in our 2014 study. The earlier report described how to calculate utility impact factors based on data from the Energy Information Agency's Annual Energy Outlook (AEO) projections of electricity supply and demand. The 2014 methodology relied on data from the AEO Reference case, and side cases implementing demand-side policies with a substantial impact on total demand. Beginning in 2015, the AEO publication schedule was revised to limit the number of side cases published with each AEO, and no suitable demand-focused side cases have been released since 2014. Hence, this paper presents a generalization of the methodology that allows a uniform approach irrespective of the nature of the side cases published with the AEO. The impact factors we calculate represent coeffcients of variation between a unit reduction to site electricity demand and corresponding supply-side changes, including reductions to electric power generation and primary fuel consumption by fuel type, emissions of criteria pollutants (Hg, NO x and SO 2 ) and greenhouse gases (CO 2 , N 2 O and CH 4 ), and total installed capacity by plant type. The impact factors are time-dependent, and also depend on the demand sector and end use. In this report, we apply the methodology to all AEO publications from 2014-2019, and all scenarios. We quantify the variation in factors across different side cases within each AEO, and across different AEO publications, and compare this to the variation due to changes in methodology.
Hg2Sn(SBr)2 crystallizes in the monoclinic P2_1/c 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 two S2- and three Br1- atoms. Both Hg–S bond lengths are 2.40 Å. There are two shorter (3.38 Å) and one longer (3.43 Å) Hg–Br bond lengths. In the second Hg2+ site, Hg2+ is bonded in a 2-coordinate geometry to three S2- and two equivalent Br1- atoms. There are a spread of Hg–S bond distances ranging from 2.40–3.08 Å. There are one shorter (3.46 Å) and one longer (3.56 Å) Hg–Br bond lengths. Sn2+ is bonded to two S2- and three Br1- atoms to form distorted edge-sharing SnS2Br3 square pyramids. There are one shorter (3.01 Å) and one longer (3.08 Å) Sn–S bond lengths. There are a spread of Sn–Br bond distances ranging from 2.84–2.96 Å. There are two inequivalent S2- sites. In the first S2- site, S2- is bonded in a 3-coordinate geometry to two Hg2+ and one Sn2+ atom. In the second S2- site, S2- is bonded in a 4-coordinate geometry to three Hg2+ and one Sn2+ atom. There are two inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a 1-coordinate geometry to four Hg2+ and one Sn2+ atom. In the second Br1- site, Br1- is bonded in a 3-coordinate geometry to one Hg2+ and two equivalent Sn2+ atoms.
Hg7(PO5)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are four inequivalent Hg+1.43+ sites. In the first Hg+1.43+ site, Hg+1.43+ is bonded in a distorted linear geometry to two equivalent O2- atoms. Both Hg–O bond lengths are 2.06 Å. In the second Hg+1.43+ site, Hg+1.43+ is bonded in a 4-coordinate geometry to four O2- atoms. There are a spread of Hg–O bond distances ranging from 2.24–2.70 Å. In the third Hg+1.43+ site, Hg+1.43+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of Hg–O bond distances ranging from 2.28–2.68 Å. In the fourth Hg+1.43+ site, Hg+1.43+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of Hg–O bond distances ranging from 2.29–2.43 Å. P5+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of P–O bond distances ranging from 1.55–1.58 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a 1-coordinate geometry to two Hg+1.43+ and one P5+ atom. In the second O2- site, O2- is bonded in a 1-coordinate geometry to two Hg+1.43+ and one P5+ atom. In the third O2- site, O2- is bonded in a 2-coordinate geometry to one Hg+1.43+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to two Hg+1.43+ and one P5+ atom. In the fifth O2- site, O2- is bonded to four Hg+1.43+ atoms to form a mixture of distorted edge and corner-sharing OHg4 tetrahedra.
Chalcogenide crystals have a wide range of applications, especially as thermoelectric materials for energy conversion. Thermoelectric materials can be used to generate an electric current from a temperature gradient based on the Seebeck effect and based on the Peltier effect, and they can be used in cooling applications. Using first-principles calculations and semiclassical Boltzmann theory, we have computed the Seebeck coefficient, electrical conductivity, electronic thermal conductivity, power factor, and figure of merit of 30 chalcogenide crystals. A Quantum Espresso package is used to calculate the electronic properties and locate the Fermi level. The transport properties are then calculated using the BoltzTraP code. The 30 crystals are divided into two groups. The first group has four crystals with quaternary composition (A 2 BCQ 4 ) (A = Tl; B = Cd, Hg; C = Si, Ge, Sn; Q = S, Se, Te). The second group contains 26 crystals with the ternary composition (A’B’Q 2 ) (A’ = Ag, Cu, Au, Na; B’ = B, Al, Ga, In; Q = S, Se, Te). Among these 30 chalcogenide crystals, the results for 11 crystals: Tl 2 CdGeSe 4 , Tl 2 CdSnSe 4 , Tl 2 HgSiSe 4 , Tl 2 HgSnS 4 , AuBSe 2 , AuBTe 2 , AuAlTe 2 , AuGaTe 2 , AuInTe 2 , AgAlSe 2 , and AgAlTe 2 are revealed for the first time. In addition, temperature-dependent transport properties of pure and doped AgSbSe 2 and AgSbTe 2 crystals with dopant compositions of AgSb 0.94 Cd 0.06 Te 2 and AgSbTe 1.85 Se 0.15 were explored. These results provide an excellent database for bulk chalcogenides crucial for a wide range of potential applications in renewable energy fields.
Hg3Al(OF3)2 crystallizes in the trigonal R-3m space group. The structure is three-dimensional. Hg is bonded in a distorted square co-planar geometry to two equivalent O and two equivalent F atoms. Both Hg–O bond lengths are 2.18 Å. Both Hg–F bond lengths are 2.55 Å. Al is bonded in an octahedral geometry to six equivalent F atoms. All Al–F bond lengths are 1.82 Å. O is bonded in a trigonal planar geometry to three equivalent Hg atoms. F is bonded in a distorted single-bond geometry to one Hg and one Al atom.
Hg3(NO4)2 crystallizes in the orthorhombic Pbca space group. The structure is three-dimensional. there are three inequivalent Hg2+ sites. In the first Hg2+ site, Hg2+ is bonded in a 2-coordinate geometry to seven O2- atoms. There are a spread of Hg–O bond distances ranging from 2.11–2.94 Å. In the second Hg2+ site, Hg2+ is bonded to five O2- atoms to form distorted corner-sharing HgO5 trigonal bipyramids. There are a spread of Hg–O bond distances ranging from 2.09–2.78 Å. In the third Hg2+ site, Hg2+ is bonded in a 2-coordinate geometry to seven O2- atoms. There are a spread of Hg–O bond distances ranging from 2.12–2.96 Å. There are two inequivalent N5+ sites. In the first N5+ site, N5+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of N–O bond distances ranging from 1.26–1.28 Å. In the second N5+ site, N5+ is bonded in a trigonal planar geometry to three O2- atoms. There is two shorter (1.27 Å) and one longer (1.28 Å) N–O bond length. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to two Hg2+ and one N5+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Hg2+ and one N5+ atom. In the third O2- site, O2- is bonded in a trigonal planar geometry to three Hg2+ atoms. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to two Hg2+ and one N5+ atom. In the fifth O2- site, O2- is bonded in a distorted single-bond geometry to three Hg2+ and one N5+ atom. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to two Hg2+ and one N5+ atom. In the seventh O2- site, O2- is bonded in a distorted single-bond geometry to two Hg2+ and one N5+ atom. In the eighth O2- site, O2- is bonded in a trigonal non-coplanar geometry to three Hg2+ atoms.
Sr(HgTl)2 crystallizes in the tetragonal P4_2/mnm space group. The structure is three-dimensional. Sr is bonded in a 12-coordinate geometry to eight Hg and four equivalent Tl atoms. There are a spread of Sr–Hg bond distances ranging from 3.58–3.70 Å. All Sr–Tl bond lengths are 3.65 Å. There are two inequivalent Hg sites. In the first Hg site, Hg is bonded in a 9-coordinate geometry to four equivalent Sr, three Hg, and two equivalent Tl atoms. There are two shorter (2.91 Å) and one longer (2.92 Å) Hg–Hg bond lengths. Both Hg–Tl bond lengths are 3.17 Å. In the second Hg site, Hg is bonded in a 8-coordinate geometry to four equivalent Sr, two equivalent Hg, and two equivalent Tl atoms. Both Hg–Tl bond lengths are 3.14 Å. Tl is bonded in a 2-coordinate geometry to two equivalent Sr, two Hg, and five equivalent Tl atoms. There are one shorter (3.20 Å) and four longer (3.38 Å) Tl–Tl bond lengths.
Hg6Cd(As2Br3)2 crystallizes in the cubic Pa-3 space group. The structure is three-dimensional. Hg2+ is bonded to two As2- and four equivalent Br1- atoms to form distorted HgAs2Br4 octahedra that share corners with eight equivalent HgAs2Br4 octahedra, corners with two AsHg3As tetrahedra, edges with two equivalent CdBr6 octahedra, and edges with four equivalent HgAs2Br4 octahedra. The corner-sharing octahedra tilt angles range from 14–88°. There are one shorter (2.60 Å) and one longer (2.61 Å) Hg–As bond lengths. There are a spread of Hg–Br bond distances ranging from 3.11–3.36 Å. Cd2+ is bonded to six equivalent Br1- atoms to form CdBr6 octahedra that share edges with twelve equivalent HgAs2Br4 octahedra. All Cd–Br bond lengths are 2.84 Å. There are two inequivalent As2- sites. In the first As2- site, As2- is bonded to three equivalent Hg2+ and one As2- atom to form AsHg3As tetrahedra that share corners with three equivalent HgAs2Br4 octahedra, corners with six equivalent BrCdHg4 square pyramids, corners with three equivalent AsHg3As tetrahedra, and edges with three equivalent BrCdHg4 square pyramids. The corner-sharing octahedral tilt angles are 70°. The As–As bond length is 2.46 Å. In the second As2- site, As2- is bonded to three equivalent Hg2+ and one As2- atom to form AsHg3As tetrahedra that share corners with three equivalent HgAs2Br4 octahedra, corners with six equivalent BrCdHg4 square pyramids, corners with three equivalent AsHg3As tetrahedra, and edges with three equivalent BrCdHg4 square pyramids. The corner-sharing octahedral tilt angles are 73°. Br1- is bonded to four equivalent Hg2+ and one Cd2+ atom to form distorted BrCdHg4 square pyramids that share corners with nine equivalent BrCdHg4 square pyramids, corners with four AsHg3As tetrahedra, edges with four equivalent BrCdHg4 square pyramids, and edges with two AsHg3As tetrahedra.
Pd5HgSe crystallizes in the tetragonal P4/mmm space group. The structure is three-dimensional. there are two inequivalent Pd sites. In the first Pd site, Pd is bonded to eight equivalent Pd and four equivalent Hg atoms to form PdHg4Pd8 cuboctahedra that share corners with four equivalent PdHg4Pd8 cuboctahedra, faces with four equivalent PdHg4Pd8 cuboctahedra, and faces with four equivalent HgPd12 cuboctahedra. All Pd–Pd bond lengths are 2.90 Å. All Pd–Hg bond lengths are 2.89 Å. In the second Pd site, Pd is bonded in a 2-coordinate geometry to two equivalent Pd, two equivalent Hg, and two equivalent Se atoms. Both Pd–Hg bond lengths are 2.90 Å. Both Pd–Se bond lengths are 2.55 Å. Hg is bonded to twelve Pd atoms to form HgPd12 cuboctahedra that share corners with four equivalent HgPd12 cuboctahedra, faces with four equivalent PdHg4Pd8 cuboctahedra, and faces with four equivalent HgPd12 cuboctahedra. Se is bonded in a body-centered cubic geometry to eight equivalent Pd atoms.
Mercury (Hg) is a heavy metal that enters the environment through natural and anthropogenic means. Once in the environment, Hg can biomagnify in food webs and is known to cause immunotoxic effects to wildlife. Compared with other vertebrates, knowledge of the reptilian immune system is lacking, especially in snakes. Further, even less is known about the impact of environmental contaminants on snake immunity. This gap in knowledge is largely due to an absence of established immune-based assays or specific reagents for these species. In this study, brown watersnakes (Nerodia taxispilota; n = 23) were captured on the Savannah River (Augusta, Georgia, USA), weighed, measured, bled, and released. Peripheral blood leukocytes (24 h old) were enriched and evaluated with an established mammalian in vitro lymphocyte proliferation assay. Enriched leukocytes were then exposed to mercury chloride (HgCl2) at 3.75, 37.5, and 75 μM. Total mercury (THg) in whole blood was also quantified. Snake peripheral blood leukocyte enrichment yielded >90% lymphocytes with viabilities averaging >70%. Exposure to HgCl 2 resulted in significant dose-dependent suppression of proliferative responses relative to spontaneous proliferation at 37.5 and 75 μM (both p ≤ 0.01) but not 3.75 μM (p = 0.99). Mean ± 1 SE concentration of THg in whole blood was 0.127 ± 0.027 mg/kg (wet weight). Based on the in vitro findings with HgCl 2 , snakes in systems with heavy Hg pollution may be at risk of immunosuppression, but N. taxispilota at the site in this study appear to be at low risk.
Hg3O2(SO4) crystallizes in the trigonal P3_1 space group. The structure is three-dimensional. there are three inequivalent Hg2+ sites. In the first Hg2+ site, Hg2+ is bonded in a 2-coordinate geometry to seven O2- atoms. There are a spread of Hg–O bond distances ranging from 2.14–2.97 Å. In the second Hg2+ site, Hg2+ is bonded in a 2-coordinate geometry to two O2- atoms. Both Hg–O bond lengths are 2.11 Å. In the third 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 2.15–2.88 Å. S6+ is bonded in a tetrahedral geometry to four O2- atoms. There is one shorter (1.49 Å) and three longer (1.50 Å) S–O bond length. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Hg2+ and one S6+ atom. In the second O2- site, O2- is bonded in a distorted single-bond geometry to two Hg2+ and one S6+ atom. In the third O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to four Hg2+ atoms. In the fourth O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Hg2+ and one S6+ atom. In the fifth O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to four Hg2+ atoms. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to one Hg2+ and one S6+ atom.
(Hg3(SO5)2)2O2 crystallizes in the monoclinic C2/c space group. The structure is two-dimensional and consists of four water molecules and two Hg3(SO5)2 sheets oriented in the (0, 0, 1) direction. In each Hg3(SO5)2 sheet, there are two inequivalent Hg sites. In the first Hg site, Hg is bonded to six O atoms to form HgO6 octahedra that share corners with four equivalent SO4 tetrahedra. There are a spread of Hg–O bond distances ranging from 2.11–2.60 Å. In the second Hg site, Hg is bonded in a distorted linear geometry to two O atoms. There are one shorter (2.05 Å) and one longer (2.09 Å) Hg–O bond lengths. S is bonded to four O atoms to form SO4 tetrahedra that share corners with two equivalent HgO6 octahedra. The corner-sharing octahedra tilt angles range from 47–64°. There are a spread of S–O bond distances ranging from 1.47–1.54 Å. There are five inequivalent O sites. In the first O site, O is bonded in a distorted single-bond geometry to one Hg and one S atom. In the second O site, O is bonded in a bent 120 degrees geometry to two Hg atoms. In the third O site, O is bonded in a bent 120 degrees geometry to one Hg and one S atom. In the fourth O site, O is bonded in a single-bond geometry to one S atom. In the fifth O site, O is bonded in a distorted bent 120 degrees geometry to one Hg and one S atom.
Na2HgPb crystallizes in the orthorhombic Cmcm space group. The structure is three-dimensional. Na is bonded in a 2-coordinate geometry to four equivalent Hg and four equivalent Pb atoms. There are two shorter (3.47 Å) and two longer (3.69 Å) Na–Hg bond lengths. There are a spread of Na–Pb bond distances ranging from 3.23–3.60 Å. Hg is bonded to eight equivalent Na, two equivalent Hg, and two equivalent Pb atoms to form a mixture of distorted face, edge, and corner-sharing HgNa8Hg2Pb2 cuboctahedra. Both Hg–Hg bond lengths are 3.08 Å. Both Hg–Pb bond lengths are 3.05 Å. Pb is bonded in a 10-coordinate geometry to eight equivalent Na and two equivalent Hg atoms.
Cs2Hg3OI8 crystallizes in the monoclinic Cm space group. The structure is three-dimensional. Cs is bonded in a 1-coordinate geometry to one O and eight I atoms. The Cs–O bond length is 3.26 Å. There are a spread of Cs–I bond distances ranging from 4.05–4.38 Å. There are two inequivalent Hg sites. In the first Hg site, Hg is bonded to four I atoms to form corner-sharing HgI4 tetrahedra. There are a spread of Hg–I bond distances ranging from 2.77–2.93 Å. In the second Hg site, Hg is bonded to four I atoms to form corner-sharing HgI4 tetrahedra. There are two shorter (2.76 Å) and two longer (2.97 Å) Hg–I bond lengths. O is bonded in a bent 120 degrees geometry to two equivalent Cs atoms. There are five inequivalent I sites. In the first I site, I is bonded in a 1-coordinate geometry to two equivalent Cs and one Hg atom. In the second I site, I is bonded in a distorted single-bond geometry to two equivalent Cs and one Hg atom. In the third I site, I is bonded in a distorted rectangular see-saw-like geometry to two equivalent Cs and two equivalent Hg atoms. In the fourth I site, I is bonded to three equivalent Cs and one Hg atom to form a mixture of distorted corner and edge-sharing ICs3Hg trigonal pyramids. In the fifth I site, I is bonded in a 2-coordinate geometry to one Cs and two Hg atoms.
BaAg2(HgO2)2 crystallizes in the tetragonal P4/nbm space group. The structure is three-dimensional. Ba2+ is bonded in a distorted body-centered cubic geometry to eight equivalent O2- atoms. All Ba–O bond lengths are 2.92 Å. Ag1+ is bonded in a linear geometry to two equivalent O2- atoms. Both Ag–O bond lengths are 2.12 Å. Hg2+ is bonded in a distorted linear geometry to four equivalent O2- atoms. There are two shorter (2.05 Å) and two longer (2.90 Å) Hg–O bond lengths. O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+, one Ag1+, and two equivalent Hg2+ atoms.
Holey graphene (HG), formed by introducing nanoscale perforations into graphene sheets, combines the structural advantages of continuous sp 2 conjugation with the beneficial effects of high surface area and enhanced chemical reactivity associated with nanoscopic holes. Conventional HG fabrication methods often rely on harsh oxidative treatments that compromise graphene's intrinsic electronic properties by disrupting its sp 2 conjugation. A new approach is introduced to fabricate HG directly from single-layer graphene (SLG), using two-dimensional covalent organic frameworks (COFs) as a template followed by controlled oxygen plasma etching. This method preserves the integrity of the SLG's sp 2 network while producing well-defined holes with an average diameter of 2.7 nm. These hole edges act as reactive sites that facilitate the confined, autoreductive growth of palladium nanoparticles (PdNPs) without external reducing agents. The confined hole geometry prevents NP agglomeration and ensures a uniform size distribution. The resulting Pd@HG hybrid exhibits exceptional chemiresistive hydrogen sensing characteristics, including ultrahigh sensitivity, low detection limits, rapid response and recovery, and long-term stability under both dry and humid conditions. Mechanistic investigations reveal a two-step sensing process involving surface redox interactions and hydrogen absorption into the PdNP lattices. This strategy presents a scalable platform for integrating metal NPs within conductive carbon frameworks for advanced sensing applications.