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Results for “Hg(OF)2”

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At least 19 records
All sourcesNASA NTRSDOE OSTI
DOE OSTI2021

Ferromagnetism out of charge fluctuation of strongly correlated electrons in κ -(BEDT-TTF) 2 Hg(SCN) 2 Br

We perform magnetic susceptibility and magnetic torque measurements on the organic κ-(BEDT-TTF) 2 Hg(SCN) 2 Br, which is recently suggested to host an exotic quantum dipole-liquid in its low-temperature insulating phase. Below the metal-insulator (MI) transition temperature, the magnetic susceptibility follows a Curie–Weiss law with a positive Curie–Weiss temperature, and a particular M∝ $\sqrt{H}$ curve is observed. The emergent ferromagnetically interacting spins amount to about 1/6 of the full spin moment of localized charges. Taking account of the possible inhomogeneous quasi-charge-order that forms a dipole-liquid, we construct a model of antiferromagnetically interacting spin chains in two adjacent charge-ordered domains, which are coupled via fluctuating charges on a Mott-dimer at the boundary. We find that the charge fluctuations can draw a weak ferromagnetic moment out of the spin singlet domains.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Probing the effect of magnetic field on charge order in the quasi-two-dimensional Mott insulator κ - (ET) 2 Hg(SCN) 2 Cl

Molecular-based quasi-two-dimensional charge-ordered Mott insulators can possess both spin S = 1/2 and an electric dipole degree of freedom residing on each (BEDT - TTF) 2 lattice site. There exists a theoretical proposal for a magnetoelectric effect in such a material, which can manifest itself as a sensitivity of charge distribution on (BEDT - TTF) 2 dimers to the magnetic field. Here in this work, we used Raman scattering spectroscopy in the magnetic field up to 31 T applied perpendicular to the two-dimensional triangular lattice planes to probe a magnetoelectric effect in $\kappa$ - (ET) 2 H g (SCN) 2 Cl. This is a model compound, which shows charge order and antiferromagnetic correlations at temperatures below 30 K. We discuss possible reasons for the absence of an observable magnetoelectric effect in the probed temperature and magnetic field ranges.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Controlling thermoelectric transport via native defects in the diamond-like semiconductors Cu 2 HgGeTe 4 and Hg 2 GeTe 4

Diamond like semiconductors (DLS) have emerged as candidates for thermoelectric energy conversion. Towards understanding and optimizing performance, we present a comprehensive investigation of the electronic properties of two DLS phases, quaternary Cu 2 HgGeTe 4 and related ordered vacancy compound Hg 2 GeTe 4 , including thermodynamic stability, defect chemistry, and transport properties. To establish the thermodynamic link between the related but distinct phases, the stability region for both is visualized in chemical potential space. In spite of their similar structure and bonding, we show that the two materials exhibit reciprocal behaviors for dopability. Cu 2 HgGeTe 4 is degenerately p-type in all environments despite its wide stability region, due to the presence of low-energy acceptor defects V Cu and Cu Hg and is resistant to extrinsic n-type doping. Meanwhile Hg 2 GeTe 4 has a narrow stability region and intrinsic behavior due to the relatively high formation energy of native defects, but presents an opportunity for bi-polar doping. While these two compounds have similar structure, bonding, and chemical constituents, the reciprocal nature of their dopability emerges from significant differences in band edge positions. A Brouwer band diagram approach is utilized to visualize the role of native defects on carrier concentrations, dopability, and transport properties. Here this study elucidates the doping asymmetry between two solid-solution forming DLS phases Cu 2 HgGeTe 4 and Hg 2 GeTe 4 by revealing the defect chemistry of each compound, and suggests design strategies for defect engineering of DLS phases.

32 ENERGY CONSERVATION, CONSUMPTION, AND UTILIZATI↗
DOE OSTI2022

Activator-doped Hg 2 Br 2 as next generation high performance scintillator for high energy physics research and other scientific and imaging applications

Existing COTS inorganic scintillators all have the characteristic of being very good at certain desirable properties, but not sufficient at other desirable properties for HEP. The demand for suitable scintillators (with regards to both scintillation detector properties and suitable pricing), to be used for modern intensities frontier (Mu2e-II), energy frontier (High luminosity large hadron collider) and future e+e- collider projects (aimed as Higgs bosons factory, such as the International Linear Collider (ILC) and the Future Circular Collider (FCC) are putting even higher challenges on crystal scintillators.In this work, we report the development of a novel high-performance scintillators that can address the issues associated with existing scintillators, the activator doped Hg2Br2. Initial results are very encouraging on the detection of gamma and alpha particles using a solid-state photomultiplier (SSPM). The responses have been stable and repeatable. Hg2Br2 also has many advantages over existing COTS scintillators such as: high density, bright, fast, good energy resolution, no intrinsic radiation, radiation hard and cost-effectiveness. Here, we present here why Hg2Br2 is the next generation scintillator for high energy physics experiments as well as other scientific and imaging applications such as planetary science and medical imaging.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Understanding Cu incorporation in the Cu 2x Hg 2-x GeTe 4 structure using resonant x-ray diffraction

The ability to control carrier concentration based on the extent of Cu solubility in the Cu 2x Hg 2-x GeTe 4 alloy compound (where 0 ≤ x ≤ 1) makes Cu 2x Hg 2-x GeTe 4 an interesting case study in the field of thermoelectrics. While Cu clearly plays a role in this process, it is unknown exactly how Cu incorporates into the Cu 2x Hg 2-x GeTe 4 crystal structure and how this affects the carrier concentration. In this work, we use a combination of resonant energy x-ray diffraction (REXD) experiments and density functional theory (DFT) calculations to elucidate the nature of Cu incorporation into the Cu 2x Hg 2-x GeTe 4 structure. REXD across the Cu k edge facilitates the characterization of Cu incorporation in the Cu 2x Hg 2-x GeTe 4 alloy and enables direct quantification of antisite defects. Here, we find that Cu substitutes for Hg at a 2:1 ratio, wherein Cu annihilates a vacancy and swaps with a Hg atom. DFT calculations confirm this result and further indicate that the incorporation of Cu occurs preferentially on one of the z = 1/4 or z = 3/4 planes before filling the other plane. Furthermore, the amount of Cu Hg antisite defects quantified by REXD was found to be directly proportional to the experimentally measured hole concentration, indicating that the Cu Hg defects are the driving force for tuning carrier concentration in the Cu 2x Hg 2-x GeTe 4 alloy. The link uncovered here between crystal structure, or more specifically antisite defects, and carrier concentration can be extended to similar cation-disordered material systems and will aid the development of improved thermoelectric and other functional materials through defect engineering.

36 MATERIALS SCIENCE↗
DOE OSTI2021

Highly efficient, rapid, and concurrent removal of toxic heavy metals by the novel 2D hybrid LDH–[Sn 2 S 6 ]

According to a United Nations report, by 2050 nearly six billion people worldwide will suffer from clean water scarcity. This is mostly because of the exponential proliferation of world population, urbanization, industrialization, and water pollution. Heavy metals are common water pollutants that can pose grave public health consequences. Existing water purification systems are lack of materials that have the potential for quick, simultaneous, efficient, and cost-efficient removal of numerous toxic metals from wastewater. Here, in this work, we report the design and synthesis of an economically viable Layered Double Hydroxides - Stannic Sulfide, LDH–[Sn 2 S 6 ] that exhibits a rapid, efficient, selective, and concurrent removal of Cu 2+ , Ag + , Cd 2+ , Pb 2+ , and Hg 2+ from parts per million (ppm) level to below 5 parts per billion (ppb) satisfying World Health Organization’s (WHO) safe drinking water limit. Moreover, LDH–[Sn 2 S 6 ] shows exceptionally high removal efficiencies of the above metals in acidic, neutral, and basic conditions. LDH–[Sn 2 S 6 ] also demonstrates enormous sorption capacities of 378, 978, 332, 579, and 666 mg/g for Cu 2+ , Ag + , Cd 2+ , Pb 2+ , and Hg 2+ , respectively. Remarkably, LDH–[Sn 2 S 6 ] displays extraordinary tolerance to the concentrations of Na + , Ca 2+ , Mg 2+ , Cl - , CO 3 2– , NO 3 – ,and SO 4 2- , and other constituents in tap and river water, it efficiently sequestrates Cu 2+ , Ag + , Cd 2+ , Pb 2+ , and Hg 2+ from ppm to safe drinking water levels in minutes. LDH–[Sn 2 S 6 ] shows pseudo-second-order sorption kinetics suggesting chemisorption adsorption mechanism involving M–S bonding. Altogether, the regeneratable LDH–[Sn 2 S 6 ] becomes an exceptional material that shows ultrahigh removal, unprecedented selectivity, rapid adsorption kinetics, wide pH stability, and a massive adsorption capacity. The integration of these features places LDH–[Sn 2 S 6 ] at the top of all adsorbents known to date and thus could be used for wastewater purifications.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2023

ATCUN-like Copper Site in βB2-Crystallin Plays a Protective Role in Cataract-Associated Aggregation

Cataract is the leading cause of blindness worldwide, and it is caused by crystallin damage and aggregation. Senile cataractous lenses have relatively high levels of metals, while some metal ions can directly induce the aggregation of human γ-crystallins. Here, for this work, we evaluated the impact of divalent metal ions in the aggregation of human βB2-crystallin, one of the most abundant crystallins in the lens. Turbidity assays showed that Pb 2+ , Hg 2+ , Cu 2+ , and Zn 2+ ions induce the aggregation of βB2-crystallin. Metal-induced aggregation is partially reverted by a chelating agent, indicating the formation of metal-bridged species. Our study focused on the mechanism of copper-induced aggregation of βB2-crystallin, finding that it involves metal-bridging, disulfide-bridging, and loss of protein stability. Circular dichroism and electron paramagnetic resonance (EPR) revealed the presence of at least three Cu 2+ binding sites in βB2-crystallin, one of them with spectroscopic features typical for Cu 2+ bound to an amino-terminal copper and nickel (ATCUN) binding motif, which is found in Cu transport proteins. The ATCUN-like Cu binding site is located at the unstructured N-terminus of βB2-crystallin, and it could be modeled by a peptide with the first six residues in the protein sequence (NH 2 -ASDHQF-). Isothermal titration calorimetry indicates a nanomolar Cu 2+ binding affinity for the ATCUN-like site. An N-truncated form of βB2-crystallin is more susceptible to Cu-induced aggregation and is less thermally stable, indicating a protective role for the ATCUN-like site. EPR and X-ray absorption spectroscopy studies reveal the presence of a copper redox active site in βB2-crystallin that is associated with metal-induced aggregation and formation of disulfide-bridged oligomers. Our study demonstrates metal-induced aggregation of βB2-crystallin and the presence of putative copper binding sites in the protein. Whether the copper-transport ATCUN-like site in βB2-crystallin plays a functional/protective role or constitutes a vestige from its evolution as a lens structural protein remains to be elucidated.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2020

Materials Data on Hg(C2F3)2 by Materials Project

Hg(CF)2(CF2)2 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two difluoromethane molecules and one Hg(CF)2 cluster. In the Hg(CF)2 cluster, Hg2+ is bonded in a distorted linear geometry to two equivalent C1+ atoms. Both Hg–C bond lengths are 2.09 Å. C1+ is bonded in a distorted single-bond geometry to one Hg2+ and one F1- atom. The C–F bond length is 1.38 Å. F1- is bonded in a single-bond geometry to one C1+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hg(OF)2 by Materials Project

Hg(OF)2 crystallizes in the orthorhombic Pbcn space group. The structure is two-dimensional and consists of two Hg(OF)2 sheets oriented in the (0, 0, 1) direction. Hg is bonded in a 8-coordinate geometry to four equivalent O and four equivalent F atoms. There are two shorter (2.29 Å) and two longer (2.39 Å) Hg–O bond lengths. There are two shorter (2.39 Å) and two longer (2.46 Å) Hg–F bond lengths. O is bonded in a water-like geometry to two equivalent Hg atoms. F is bonded in a water-like geometry to two equivalent Hg atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hg(ClO3)2 by Materials Project

Hg(O3Cl)2 crystallizes in the monoclinic P2_1 space group. The structure is one-dimensional and consists of two Hg(O3Cl)2 ribbons oriented in the (0, 1, 0) direction. Hg is bonded in a 4-coordinate geometry to four O atoms. There are a spread of Hg–O bond distances ranging from 2.25–2.54 Å. There are six inequivalent O sites. In the first O site, O is bonded in a distorted L-shaped geometry to one Hg and one Cl atom. The O–Cl bond length is 1.50 Å. In the second O site, O is bonded in a water-like geometry to one Hg and one Cl atom. The O–Cl bond length is 1.56 Å. In the third O site, O is bonded in a bent 120 degrees geometry to one Hg and one Cl atom. The O–Cl bond length is 1.60 Å. In the fourth O site, O is bonded in a water-like geometry to one Hg and one Cl atom. The O–Cl bond length is 1.50 Å. In the fifth O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.49 Å. In the sixth O site, O is bonded in a single-bond geometry to one Cl atom. The O–Cl bond length is 1.48 Å. There are two inequivalent Cl sites. In the first Cl site, Cl is bonded in a trigonal non-coplanar geometry to three O atoms. In the second Cl site, Cl is bonded in a trigonal non-coplanar geometry to three O atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hg(BrO4)2 by Materials Project

Hg(O4Br)2 crystallizes in the orthorhombic P2_12_12_1 space group. The structure is one-dimensional and consists of two Hg(O4Br)2 ribbons oriented in the (0, 1, 0) direction. Hg is bonded in a 6-coordinate geometry to six O atoms. There are a spread of Hg–O bond distances ranging from 2.06–2.62 Å. There are eight inequivalent O sites. In the first O site, O is bonded in a single-bond geometry to one Br atom. The O–Br bond length is 1.68 Å. In the second O site, O is bonded in a single-bond geometry to one Hg atom. In the third O site, O is bonded in a single-bond geometry to one Hg atom. In the fourth O site, O is bonded in a single-bond geometry to one Br atom. The O–Br bond length is 1.66 Å. In the fifth O site, O is bonded in a water-like geometry to one Hg and one Br atom. The O–Br bond length is 1.70 Å. In the sixth O site, O is bonded in a 1-coordinate geometry to two equivalent Hg and one Br atom. The O–Br bond length is 1.73 Å. In the seventh O site, O is bonded in a bent 120 degrees geometry to one Hg and one Br atom. The O–Br bond length is 1.71 Å. In the eighth O site, O is bonded in a single-bond geometry to one Br atom. The O–Br bond length is 1.67 Å. There are two inequivalent Br sites. In the first Br site, Br is bonded in a trigonal non-coplanar geometry to three O atoms. In the second Br site, Br is bonded in a trigonal non-coplanar geometry to three O atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hg(PO3)2 by Materials Project

Hg(PO3)2 crystallizes in the orthorhombic Pbca space group. The structure is three-dimensional. Hg2+ is bonded in a 6-coordinate geometry to six O2- atoms. There are a spread of Hg–O bond distances ranging from 2.23–2.63 Å. There are two inequivalent P5+ sites. In the first P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.61 Å. In the second P5+ site, P5+ is bonded to four O2- atoms to form corner-sharing PO4 tetrahedra. There are a spread of P–O bond distances ranging from 1.50–1.62 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to two P5+ atoms. In the second O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Hg2+ and one P5+ atom. In the third O2- site, O2- is bonded in a 1-coordinate geometry to two equivalent Hg2+ and one P5+ atom. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to one Hg2+ and one P5+ atom. In the fifth O2- site, O2- is bonded in a bent 120 degrees geometry to two P5+ atoms. In the sixth O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Hg2+ and one P5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hg(TeO3)2 by Materials Project

Hg(TeO3)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. Hg2+ is bonded in a 5-coordinate geometry to five O2- atoms. There are a spread of Hg–O bond distances ranging from 2.25–2.55 Å. There are two inequivalent Te5+ sites. In the first Te5+ site, Te5+ is bonded to five O2- atoms to form a mixture of edge and corner-sharing TeO5 trigonal bipyramids. There are a spread of Te–O bond distances ranging from 1.87–2.05 Å. In the second Te5+ site, Te5+ is bonded to five O2- atoms to form a mixture of distorted edge and corner-sharing TeO5 square pyramids. There are a spread of Te–O bond distances ranging from 1.85–2.53 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a 3-coordinate geometry to one Hg2+ and two Te5+ atoms. In the second O2- site, O2- is bonded in a water-like geometry to one Hg2+ and one Te5+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to one Hg2+ and two Te5+ atoms. In the fourth O2- site, O2- is bonded in a 3-coordinate geometry to one Hg2+ and two Te5+ atoms. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to one Hg2+ and one Te5+ atom. In the sixth O2- site, O2- is bonded in a bent 150 degrees geometry to two Te5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hg(SbO3)2 by Materials Project

Hg(SbO3)2 is zeta iron carbide-derived structured and crystallizes in the trigonal P-31m space group. The structure is three-dimensional. Hg2+ is bonded to six equivalent O2- atoms to form HgO6 octahedra that share corners with twelve equivalent SbO6 octahedra. The corner-sharing octahedral tilt angles are 53°. All Hg–O bond lengths are 2.44 Å. Sb5+ is bonded to six equivalent O2- atoms to form SbO6 octahedra that share corners with six equivalent HgO6 octahedra and edges with three equivalent SbO6 octahedra. The corner-sharing octahedral tilt angles are 53°. All Sb–O bond lengths are 2.02 Å. O2- is bonded in a distorted trigonal planar geometry to one Hg2+ and two equivalent Sb5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hg(SbO3)2 by Materials Project

Hg(SbO3)2 is zeta iron carbide-derived structured and crystallizes in the tetragonal P4_2/mnm space group. The structure is three-dimensional. Hg2+ is bonded to six O2- atoms to form HgO6 octahedra that share corners with eight equivalent SbO6 octahedra and edges with two equivalent SbO6 octahedra. The corner-sharing octahedra tilt angles range from 54–57°. There are two shorter (2.27 Å) and four longer (2.35 Å) Hg–O bond lengths. Sb5+ is bonded to six O2- atoms to form SbO6 octahedra that share corners with four equivalent HgO6 octahedra, corners with four equivalent SbO6 octahedra, an edgeedge with one HgO6 octahedra, and an edgeedge with one SbO6 octahedra. The corner-sharing octahedra tilt angles range from 39–57°. There are four shorter (2.03 Å) and two longer (2.05 Å) Sb–O bond lengths. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a trigonal planar geometry to one Hg2+ and two equivalent Sb5+ atoms. In the second O2- site, O2- is bonded in a 3-coordinate geometry to one Hg2+ and two equivalent Sb5+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hg(IO3)2 by Materials Project

Hg(IO3)2 crystallizes in the monoclinic P2_1 space group. The structure is three-dimensional. Hg2+ is bonded in a 8-coordinate geometry to eight O2- atoms. There are a spread of Hg–O bond distances ranging from 2.25–2.97 Å. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted single-bond geometry to one Hg2+ and two I5+ atoms. There are one shorter (1.84 Å) and one longer (2.60 Å) O–I bond lengths. In the second O2- site, O2- is bonded in a distorted single-bond geometry to two equivalent Hg2+ and two equivalent I5+ atoms. There are one shorter (1.83 Å) and one longer (2.71 Å) O–I bond lengths. In the third O2- site, O2- is bonded in a 2-coordinate geometry to one Hg2+ and two I5+ atoms. There are one shorter (1.86 Å) and one longer (2.79 Å) O–I bond lengths. In the fourth O2- site, O2- is bonded in a 1-coordinate geometry to one Hg2+ and two equivalent I5+ atoms. There are one shorter (1.84 Å) and one longer (2.66 Å) O–I bond lengths. In the fifth O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Hg2+ and one I5+ atom. The O–I bond length is 1.88 Å. In the sixth O2- site, O2- is bonded in a 2-coordinate geometry to one Hg2+ and two I5+ atoms. There are one shorter (1.86 Å) and one longer (2.64 Å) O–I bond lengths. There are two inequivalent I5+ sites. In the first I5+ site, I5+ is bonded to six O2- atoms to form distorted corner-sharing IO6 octahedra. The corner-sharing octahedral tilt angles are 48°. In the second I5+ site, I5+ is bonded in a 5-coordinate geometry to five O2- atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Hg(CO2)2 by Materials Project

Hg(CO2)2 crystallizes in the monoclinic P2_1 space group. The structure is zero-dimensional and consists of two mercuric formate molecules. Hg2+ is bonded in a distorted linear geometry to two O2- atoms. Both Hg–O bond lengths are 2.13 Å. There are two inequivalent C3+ sites. In the first C3+ site, C3+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.24 Å) and one longer (1.30 Å) C–O bond length. In the second C3+ site, C3+ is bonded in a bent 120 degrees geometry to two O2- atoms. There is one shorter (1.24 Å) and one longer (1.30 Å) C–O bond length. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one C3+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C3+ atom. In the third O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Hg2+ and one C3+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Hg2+ and one C3+ atom.

36 MATERIALS SCIENCE↗