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Cl2 is Cubic alpha N2-like structured and crystallizes in the orthorhombic Cmce space group. The structure is zero-dimensional and consists of four chlorine molecules. Cl is bonded in a single-bond geometry to one Cl atom. The Cl–Cl bond length is 2.01 Å.
Cl2 is Cubic alpha N2-like structured and crystallizes in the tetragonal P4_2/ncm space group. The structure is zero-dimensional and consists of eight molecular chlorine molecules. Cl is bonded in a single-bond geometry to one Cl atom. The Cl–Cl bond length is 1.99 Å.
Cl2 is Cubic alpha N2-like structured and crystallizes in the orthorhombic Cmce space group. The structure is zero-dimensional and consists of four molecular chlorine molecules. Cl is bonded in a single-bond geometry to one Cl atom. The Cl–Cl bond length is 2.01 Å.
Chlorine gas (Cl2) is a highly toxic chemical associated with both localized lung injury and systemic health effects. While pulmonary damage has been well characterized, the systemic inflammatory and metabolic responses remain poorly understood. We aimed to define the temporal and multi-organ responses to Cl2 exposure in a murine model, with a focus on identifying spatiotemporal inflammation and its impact on survival and lethality. SKH1 mice were exposed for 10 min to varying concentrations of Cl2 (94.4–810 ppm, representative of non-lethal, LD10, and LD50 doses) and monitored for respiratory function, perfusion, and acidosis using organ-specific imaging. At multiple time points (40 min, 6 h, 24 h, and 7 d), we measured phosphoproteins, cytokines, chemokines, growth factors, and metabolic hormones in the lungs, heart, cortex, and plasma. Statistical modeling and logistic regression were used to identify biomarkers associated with lethality and survival. We found that lung injury was the primary cause of potential lethality, particularly via early phosphoprotein signaling disruptions. However, survival correlated with early systemic coordination of inflammatory and metabolic signals across organs. Perfusion and acidosis imaging were strongly associated with chemokine and hormone responses. Key survival-associated plasma biomarkers included decreased insulin, increased ghrelin, and decreased eotaxin. While potential lethality from Cl2 exposure is locally driven by pulmonary injury, survival depends on systemic, multi-organ responses that occur rapidly post-exposure. Within this model, our findings identify a potential therapeutic window to enhance survival and suggest candidate biomarkers that may be explored translationally for both triage and treatment of chlorine-related incidents.
The molten salt reactor concept, where nuclear fuel is dissolved in a molten salt that also serves as the heat transfer fluid, is a leading candidate for next generation nuclear reactors. This necessitates a thorough understanding of radiation effects on molten salt media to support the design, development, and deployment of such reactors. Early, pioneering pulse radiolysis molten salt experiments observed key primary radiolysis products such as the solvated electron (esolv?) and dichloride radical anion (Cl2??), but left many fundamental mechanistic and reactivity questions unanswered. Here we report on the reaction kinetics of esolv? and Cl2?? in molten LiCl-KCl eutectic salt doped with Zn2+ ion, using electron pulse radiolysis to observe the transient behavior from nanosecond to microsecond time scales. Experiments were performed at the BNL Laser-Electron Accelerator Facility using a recently-developed high-temperature sample holder. Prompt formation of esolv? and Cl2?? are observed; esolv? decays within hundreds of nanoseconds while Cl2?? decays more slowly by second-order kinetics, more likely by cross-recombination rather than disproportionation. This work was supported as part of the Molten Salts in Extreme Environments Energy Frontier Research Center funded by the U.S. Department of Energy, Office of Science.
Air-side economizers are increasingly used to take advantage of “free-cooling” in data centers with the intent of reducing the carbon footprint of buildings. However, they can introduce outdoor pollutants to indoor environment of data centers and cause corrosion damage to the information technology equipment. Here, to evaluate the reliability of information technology equipment under various thermal and air-pollution conditions, a mechanistic model based on multi-ion transport and chemical reactions was developed. The model was used to predict Cu corrosion caused by Cl2-containing pollutant mixtures. It also accounted for the effects of temperature (25 °C and 28 °C), relative humidity (50%, 75%, and 95%), and synergism. It also identified higher air temperature as a corrosion barrier and higher relative humidity as a corrosion accelerator, which agreed well with the experimental results. The average root mean square error of the prediction was 13.7 Å. The model can be used to evaluate the thermal guideline for data centers design and operation when Cl2 is present based on pre-established acceptable risk of corrosion in data centers’ environment.
(NH2)2(NH3)2Cl2 crystallizes in the orthorhombic Fdd2 space group. The structure is one-dimensional and consists of sixteen ammonia molecules; sixteen ammonia molecules; and sixteen Cl2 ribbons oriented in the (1, 0, 0) direction. In each Cl2 ribbon, Cl1- is bonded in a distorted linear geometry to two equivalent Cl1- atoms. Both Cl–Cl bond lengths are 1.82 Å.
CuZn(TeO3)Cl2 crystallizes in the orthorhombic Pccn space group. The structure is two-dimensional and consists of two CuZn(TeO3)Cl2 sheets oriented in the (0, 0, 1) direction. Cu2+ is bonded in a distorted rectangular see-saw-like geometry to four O2- atoms. There are a spread of Cu–O bond distances ranging from 1.95–2.03 Å. Zn2+ is bonded in a distorted trigonal pyramidal geometry to two O2- and two Cl1- atoms. There are one shorter (2.01 Å) and one longer (2.05 Å) Zn–O bond lengths. Both Zn–Cl bond lengths are 2.24 Å. Te4+ is bonded in a 3-coordinate geometry to three O2- atoms. There are a spread of Te–O bond distances ranging from 1.92–1.95 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a trigonal planar geometry to one Cu2+, one Zn2+, and one Te4+ atom. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to one Cu2+, one Zn2+, and one Te4+ atom. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to two equivalent Cu2+ and one Te4+ atom. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a 1-coordinate geometry to one Zn2+ atom. In the second Cl1- site, Cl1- is bonded in a distorted single-bond geometry to one Zn2+ atom.
(BeO)2Cl2 crystallizes in the trigonal R-3m space group. The structure is two-dimensional and consists of six BeO sheets oriented in the (0, 0, 1) direction and six Cl2 sheets oriented in the (0, 0, 1) direction. In each BeO sheet, Be is bonded in a trigonal planar geometry to three equivalent O atoms. All Be–O bond lengths are 1.56 Å. O is bonded in a trigonal planar geometry to three equivalent Be atoms. In each Cl2 sheet, Cl is bonded in a hexagonal planar geometry to six equivalent Cl atoms. All Cl–Cl bond lengths are 2.71 Å.
(BeO)2Cl2 crystallizes in the trigonal R-3m space group. The structure is two-dimensional and consists of six BeO sheets oriented in the (0, 0, 1) direction and six Cl2 sheets oriented in the (0, 0, 1) direction. In each BeO sheet, Be is bonded in a trigonal planar geometry to three equivalent O atoms. All Be–O bond lengths are 1.56 Å. O is bonded in a trigonal planar geometry to three equivalent Be atoms. In each Cl2 sheet, Cl is bonded in a hexagonal planar geometry to six equivalent Cl atoms. All Cl–Cl bond lengths are 2.70 Å.
(S)6Cl2 crystallizes in the hexagonal P6_3/mmc space group. The structure is one-dimensional and consists of six hydrogen sulfide molecules and two Cl2 ribbons oriented in the (0, 0, 1) direction. In each Cl2 ribbon, Cl1- is bonded in a linear geometry to two equivalent Cl1- atoms. Both Cl–Cl bond lengths are 2.94 Å.
Pyrochemical reprocessing technologies can be used to recover valuable materials from used nuclear fuel (UNF), such as uranium. However, other critical materials, such as fission product neodymium, are challenging to recover from molten chloride eutectic mixtures (LiCl-KCl) due to the presence of multivalent states (Nd2+/Nd3+), disproportionation reactions, and re-dissolution in the molten chloride salt. Understanding, predicting, and controlling these processes is further complicated by the presence of ionizing radiation fields, for which little is known on the interaction of neodymium ions with the radiolytic transients (es– and Cl2.–) in molten LiCl-KCl salt mixtures. Here, chemical kinetics, from integrated electron pulse irradiation and transient absorption spectroscopy, are presented for the reaction of Nd3+ ions with es– and Cl2.– as a function of temperature (400–600 ?).
The ability to controllably chlorinate metal-oxide surfaces can provide opportunities for designing selective oxidation catalysts. In the present study, we investigated the surface chlorination of IrO2(110) by HCl using temperature programmed reaction spectroscopy (TPRS), x-ray photoelectron spectroscopy (XPS), and density functional theory (DFT) calculations. We find that exposing IrO2(110) to HCl, followed by heating to 650 K in ultrahigh vacuum, produces nearly equal quantities of on-top and bridging Cl atoms on the surface, Clt and Clbr, where the Clbr atoms replace O-atoms that are removed from the surface by H2O formation. After HCl adsorption at 85 K, only H2O desorbs at low Cl coverages during TPRS, but HCl begins to desorb in increasing yields as the Cl coverage is increased above about 0.5 monolayer (ML). The desorption of Cl2 was not observed under any conditions, in good agreement with the high barrier for this reaction predicted by DFT. A maximum Cl coverage of 1 ML, with nearly equal coverages of Clt and Clbr atoms, could be generated by reacting HCl with IrO2(110) in UHV. Our results suggest that a kinetic competition between recombinative HCl and H2O desorption under the conditions studied limits the saturation Cl coverage to a value less than the 2 ML maximum predicted by thermodynamics. XPS further shows that the partitioning of Cl between the Clt and Clbr states can be altered by subjecting partially chlorinated IrO2(110) to reductive or oxidative treatments, demonstrating that the Cl site population can change dynamically in response to the gas environment. Our results provide insights for understanding the chlorination of IrO2(110) by HCl and can enable future experimental studies to determine how Cl-modification alters the surface chemical reactivity of IrO2(110) and potentially enhances selectivity toward partial oxidation chemistry.
A dry etching process to transfer the pattern of a photonic integrated circuit design for high-speed laser communications is described. The laser stack under consideration is a 3.2-µm-thick InGaAs/InAlAs/InAlGaAs epitaxial structure grown by molecular beam epitaxy. The etching was performed using Cl2-based inductively-coupled-plasma and reactive-ion-etching (ICP-RIE) reactors. Four different recipes are presented in two similar ICP-RIE reactors, with special attention paid to the etched features formed with various hard mask compositions, in-situ passivations, and process temperatures. The results indicate that it is possible to produce high-aspect-ratio features with sub-micron separation on this multilayer structure. Additionally, the results of the etching highlight the tradeoffs involved with the corresponding recipes.
IrF6(Cl2)2 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four chlorine molecules and two IrF6 clusters. In each IrF6 cluster, Ir is bonded in an octahedral geometry to six F atoms. There is four shorter (1.89 Å) and two longer (1.90 Å) Ir–F bond length. There are three inequivalent F sites. In the first F site, F is bonded in a single-bond geometry to one Ir atom. In the second F site, F is bonded in a single-bond geometry to one Ir atom. In the third F site, F is bonded in a single-bond geometry to one Ir atom.
Sr3(SeO3)(Se2O5)Cl2 crystallizes in the orthorhombic Pnma space group. The structure is three-dimensional. there are three inequivalent Sr2+ sites. In the first Sr2+ site, Sr2+ is bonded in a 10-coordinate geometry to eight O2- and two equivalent Cl1- atoms. There are a spread of Sr–O bond distances ranging from 2.62–2.95 Å. There are one shorter (3.15 Å) and one longer (3.33 Å) Sr–Cl bond lengths. In the second Sr2+ site, Sr2+ is bonded in a 8-coordinate geometry to five O2- and three equivalent Cl1- atoms. There are a spread of Sr–O bond distances ranging from 2.56–2.60 Å. There are one shorter (3.04 Å) and two longer (3.12 Å) Sr–Cl bond lengths. In the third Sr2+ site, Sr2+ is bonded in a 9-coordinate geometry to eight O2- and one Cl1- atom. There are a spread of Sr–O bond distances ranging from 2.59–2.98 Å. The Sr–Cl bond length is 3.12 Å. There are three inequivalent Se4+ sites. In the first Se4+ site, Se4+ is bonded in a distorted trigonal non-coplanar geometry to three O2- atoms. There is one shorter (1.72 Å) and two longer (1.74 Å) Se–O bond length. In the second Se4+ site, Se4+ is bonded in a distorted T-shaped geometry to three O2- atoms. There is two shorter (1.70 Å) and one longer (1.88 Å) Se–O bond length. In the third Se4+ site, Se4+ is bonded in a distorted trigonal non-coplanar geometry to three O2- atoms. There is two shorter (1.69 Å) and one longer (1.87 Å) Se–O bond length. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one Se4+ atom. In the second O2- site, O2- is bonded in a 3-coordinate geometry to two Sr2+ and one Se4+ atom. In the third O2- site, O2- is bonded to three Sr2+ and one Se4+ atom to form a mixture of distorted edge and corner-sharing OSr3Se tetrahedra. In the fourth O2- site, O2- is bonded in a 4-coordinate geometry to three Sr2+ and one Se4+ atom. In the fifth O2- site, O2- is bonded in a distorted bent 120 degrees geometry to two equivalent Sr2+ and two Se4+ atoms. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a distorted see-saw-like geometry to four Sr2+ atoms. In the second Cl1- site, Cl1- is bonded in a distorted bent 150 degrees geometry to two equivalent Sr2+ atoms.
(Cu2H8O4Cl5)2(NH4)8(Cl2)3 crystallizes in the triclinic P1 space group. The structure is one-dimensional and consists of four ammonium molecules; three hydrochloric acid molecules; and one Cu2H8O4Cl5 ribbon oriented in the (0, 0, 1) direction. In the Cu2H8O4Cl5 ribbon, there are two inequivalent Cu2+ sites. In the first Cu2+ site, Cu2+ is bonded in a distorted rectangular see-saw-like geometry to two O2- and two Cl1- atoms. There is one shorter (1.98 Å) and one longer (1.99 Å) Cu–O bond length. There are one shorter (2.24 Å) and one longer (2.28 Å) Cu–Cl bond lengths. In the second Cu2+ site, Cu2+ is bonded in a 4-coordinate geometry to two O2- and three Cl1- atoms. Both Cu–O bond lengths are 2.00 Å. There are a spread of Cu–Cl bond distances ranging from 2.24–2.91 Å. There are eight inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- and one Cl1- atom. The H–O bond length is 1.00 Å. The H–Cl bond length is 2.07 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- and one Cl1- atom. The H–O bond length is 1.00 Å. The H–Cl bond length is 2.06 Å. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the seventh H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. In the eighth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal planar geometry to one Cu2+ and two H1+ atoms. In the second O2- site, O2- is bonded in a distorted trigonal planar geometry to one Cu2+ and two H1+ atoms. In the third O2- site, O2- is bonded in a distorted trigonal planar geometry to one Cu2+ and two H1+ atoms. In the fourth O2- site, O2- is bonded in a distorted trigonal planar geometry to one Cu2+ and two H1+ atoms. There are five inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Cu2+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Cu2+ atom. In the third Cl1- site, Cl1- is bonded in a single-bond geometry to one Cu2+ atom. In the fourth Cl1- site, Cl1- is bonded in a single-bond geometry to one Cu2+ atom. In the fifth Cl1- site, Cl1- is bonded in a 3-coordinate geometry to one Cu2+ and two H1+ atoms.
(OsH12(N3O2)2)2H2O(Cl2)2 crystallizes in the monoclinic C2/c space group. The structure is zero-dimensional and consists of sixteen hydrochloric acid molecules, four water molecules, and eight OsH12(N3O2)2 clusters. In each OsH12(N3O2)2 cluster, Os8+ is bonded in an octahedral geometry to five N+1.67- and one O2- atom. There are a spread of Os–N bond distances ranging from 1.74–2.16 Å. The Os–O bond length is 2.05 Å. There are six inequivalent N+1.67- sites. In the first N+1.67- site, N+1.67- is bonded in a distorted trigonal non-coplanar geometry to one Os8+ and three H1+ atoms. There is one shorter (1.02 Å) and two longer (1.04 Å) N–H bond length. In the second N+1.67- site, N+1.67- is bonded in a trigonal planar geometry to three O2- atoms. There is two shorter (1.23 Å) and one longer (1.37 Å) N–O bond length. In the third N+1.67- site, N+1.67- is bonded in a linear geometry to one Os8+ and one O2- atom. The N–O bond length is 1.18 Å. In the fourth N+1.67- site, N+1.67- is bonded in a distorted trigonal non-coplanar geometry to one Os8+ and three H1+ atoms. All N–H bond lengths are 1.03 Å. In the fifth N+1.67- site, N+1.67- is bonded in a trigonal non-coplanar geometry to one Os8+ and three H1+ atoms. All N–H bond lengths are 1.03 Å. In the sixth N+1.67- site, N+1.67- is bonded in a trigonal non-coplanar geometry to one Os8+ and three H1+ atoms. There is two shorter (1.03 Å) and one longer (1.04 Å) N–H bond length. There are twelve inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N+1.67- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N+1.67- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one N+1.67- atom. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one N+1.67- atom. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one N+1.67- atom. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one N+1.67- atom. In the seventh H1+ site, H1+ is bonded in a single-bond geometry to one N+1.67- atom. In the eighth H1+ site, H1+ is bonded in a single-bond geometry to one N+1.67- atom. In the ninth H1+ site, H1+ is bonded in a single-bond geometry to one N+1.67- atom. In the tenth H1+ site, H1+ is bonded in a single-bond geometry to one N+1.67- atom. In the eleventh H1+ site, H1+ is bonded in a single-bond geometry to one N+1.67- atom. In the twelfth H1+ site, H1+ is bonded in a single-bond geometry to one N+1.67- atom. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one N+1.67- atom. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to one Os8+ and one N+1.67- atom. In the third O2- site, O2- is bonded in a single-bond geometry to one N+1.67- atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one N+1.67- atom.