Engineering Papers⌕ Search

SEARCH · Engineering Papers

Results for “ClO”

Search indexed NASA NTRS and DOE OSTI research on propulsion, heat transfer, battery materials and energy systems. Follow report and document links to the original sources.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 records

Origin of the isotopic composition of natural perchlorate: Experimental results for the impact of reaction pathway and initial ClO x reactant

Natural perchlorate (ClO 4 - ) exists in many places on Earth, in lunar regolith, meteorites, and on the surface of Mars. Terrestrial natural ClO 4 - has widely variable Cl and O stable isotopic compositions (δ 37 Cl, δ 18 O, Δ 17 O). The δ 18 O and Δ 17 O values of ClO 4 - from the most hyper-arid locations co-vary. ClO 4 - from less arid areas has relatively little 17 O excess and poor Δ 17 O-δ 18 O correlation. ClO 4 - from the Atacama Desert has unusually low δ 37 Cl (<-10‰) and exhibits a positive correlation between δ 37 Cl and δ 18 O, while the δ 37 Cl of ClO 4 - from all other locations varies between -5 and +7‰ with no δ 37 Cl-δ 18 O covariation. To evaluate the impact of different precursors (ClO x ) and reaction pathways on the isotopic composition of ClO 4 - , we measured the isotopic composition of ClO 4 - produced in the laboratory by UV or O 3 mediated aqueous oxidation of Cl-, OCl-, ClO2-, and ClO2° as well as O 3 mediated oxidation of dry NaCl. ClO x oxidation in aqueous or dry systems enriched in O 3 produced ClO 4 - with Δ 17 O values that generally increased with the number of O atoms required and included evidence that the site-specific 17 O anomaly in O 3 was preferentially transferred to ClO 4 - . Based on the inferred number of O atoms sourced from O 3 , and known Cl and O reaction pathways, it appears that ClO 2 ° and ClO 3 * were required intermediates in the production of ClO 4 - in the O 3 experiments. ClO x aqueous oxidation by UV irradiation produced ClO 4 - with a large range of δ 18 O values and little or no 17 O anomaly. ClO 3 - was produced to a much greater extent than ClO 4 - in all experiments except dry oxidation of NaCl by O 3 . The isotopic composition of ClO 3 - was distinct from that of ClO 4 - produced from the same initial reactants. Combined results of O 3 and UV mediated reactions largely bracketed the range of natural ClO 4 - δ 18 O and Δ 17 O values as well as δ 37 Cl values of non-Atacama natural samples, but no conditions produced the low δ 37 Cl values of Atacama ClO 4 - . Finally, our results indicate that variation in production mechanisms, possibly combined with isotopically variable precursors, could be responsible for much of the observed isotopic variation in natural ClO 4 - and ClO 3 - .

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Reactions of U(DMSO) 8 (ClO 4 ) 4 with Terpyridine Yield Dimeric Hydrolysis Products and Induce C–C Coupling

Reactions have been carried out using UIV(DMSO) 8 (ClO 4 ) 4 with 2,2′:6′,2″-terpyridine (terpy) under nonaqueous conditions. At room temperature in acetonitrile, the combination of the U(IV) starting material with terpy resulted in a mixture containing [UO 2 (DMSO) 2 terpy][ClO 4 ] 2 ·MeCN, while increasing the water content led to the hydrolysis products [(UO 2 (DMSO)terpy) 2 (μ 2 –O)][ClO 4 ] 2 and [(UO 2 terpy) 2 (μ 2 –OH) 2 ][ClO 4 ] 2 ·MeCN·H 2 O. Performing the reaction at slightly elevated temperature with no added water led to the formation of [UO 2 sexipyridine][ClO 4 ] 2 ·MeCN. This new uranyl complex contains the hexadentate ligand 2,2′:6′,2″:6″,2″:6‴,2⁗:6⁗,2⁗′-sexipyridine, which formed in situ from the tetravalent uranium starting material, where photoexcited uranyl or in situ generated peroxide could have induced C–C coupling. Analysis of bonding in the dimeric uranyl species via quantum chemical methods revealed a small increase in covalency of the bridging oxo unit and a slightly greater stability compared to the bridging hydroxo compound, which causes a significant shift in the uranyl symmetric stretch in the Raman spectrum. Structural, spectroscopic, and computational comparisons are made across the series of compounds, providing insight into the bonding and reactivity of uranium in nonaqueous media.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Quantum magnetism in the frustrated square lattice oxyhalides YbBi 2 IO 4 and YbBi 2 ClO 4

Square-lattice systems offer a direct route for realizing two-dimensional (2D) quantum magnetism with frustration induced by competing interactions. In this work, the square lattice materials YbBi 2 IO 4 and YbBi 2 ClO 4 were investigated using a combination of magnetization and specific-heat measurements on polycrystalline samples. Specific-heat measurements provide evidence for long-range magnetic order below $T$ N = 0.21 K (0.25 K) for YbBi 2 IO 4 (YbBi 2 ClO 4 ). On the other hand, a rather broad maximum is found in the temperature-dependent magnetic susceptibility, located at $T$ max = 0.33 K (0.38 K) in YbBi 2 IO 4 (YbBi 2 ClO 4 ), consistent with the quasi-2D magnetism expected for the large separation between the magnetic layers. Estimation of the magnetic entropy supports the expected Kramers' doublet ground state for Yb 3+ and the observed paramagnetic behavior is consistent with a well-isolated doublet. Roughly two-thirds of the entropy is consumed above $T$ N , due to a combination of the quasi-2D behavior and magnetic frustration. The impact of frustration is examined from the viewpoint of a simplified $J$ 1 -$J$ 2 square lattice model, which is frustrated for antiferromagnetic interactions. Specifically, a high-temperature series expansion analysis of the temperature-dependent specific-heat and magnetization data yields $J$ 2 /$J$ 1 = 0.30 (=0.23) for YbBi 2 IO 4 (YbBi 2 ClO 4 ). In conclusion, this simplified analysis suggests strong frustration that should promote significant quantum fluctuations in these compounds, and thus motivates future work on the static and dynamic magnetic properties of these materials.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

Materials Data on Ca(ClO)2 by Materials Project

Ca(ClO)2 crystallizes in the orthorhombic Ccce space group. The structure is one-dimensional and consists of four Ca(ClO)2 ribbons oriented in the (1, 0, 0) direction. Ca is bonded in a 4-coordinate geometry to four equivalent O atoms. There are two shorter (2.34 Å) and two longer (2.38 Å) Ca–O bond lengths. O is bonded in a 3-coordinate geometry to two equivalent Ca and one Cl atom. The O–Cl bond length is 1.71 Å. Cl is bonded in a single-bond geometry to one O atom.

36 MATERIALS SCIENCE↗

Correlating Mechanical Sensitivity with Spin Transition in the Explosive Spin Crossover Complex [Fe(Htrz) 3 ] n [ClO 4 ] 2 n

Spin crossover complexes are known to undergo bond length, volume, and enthalpy changes during spin transition. In an explosive spin crossover complex, these changes could affect the mechanical and initiation sensitivity of the explosive and lead to the development of a new class of sensitivity switchable materials. To explore this relationship, the well-known spin crossover compound [Fe(Htrz) 3 ] n [ClO 4 ] 2n (1) was re-evaluated for its explosive properties, and its mechanical impact sensitivity was correlated to spin transition. A variable temperature impact test was developed and used to evaluate the impact sensitivity of 1 in the low spin (LS, S = 0), thermally accessed high spin (HS, S = 2), and mixed LS and HS states. For comparison, the structurally similar Ni compound, [Ni(Htrz) 3 ] n [ClO 4 ] 2n (2), which does not undergo a spin transition at accessible temperatures, was synthesized and characterized, and its explosive properties and variable temperature impact sensitivity measured. These results reveal a correlation between impact sensitivity and spin transition, where 1 exhibits lower impact sensitivity in the LS state and increases in sensitivity upon transition to the HS state. Here, density functional theory was used to predict structural changes that occur upon spin transition that correlate to the change in sensitivity. This demonstrates, for the first time, an explosive spin crossover compound (ExSCO) that exhibits switchable impact sensitivity with a fully reversible internal switching mechanism.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Crystal field splittings and magnetic ground state of the square-lattice antiferromagnets YbBi 2 ⁢ClO 4 and YbBi 2 ⁢IO 4 with J eff = $\frac{1}{2}$

Here, we report on the crystal field level splitting and magnetic ground state of the J eff = $\frac{1}{2}$ square lattice antiferromagnets YbBi 2 ⁢ClO 4 and YbBi 2 ⁢IO 4 using powder inelastic neutron scattering (INS) and neutron diffraction measurements. Both compounds exhibit a well-isolated Γ 7 doublet ground state under a tetragonal crystal field environment, confirming a robust J eff = $\frac{1}{2}$ picture with slight XY-type anisotropic character in the g-tensor. Notably, the ground state wave functions closely resemble the Γ 7 doublet expected in the perfect cubic limit, consistent with the nearly cubic ligand configuration of eight O 2- ions surrounding Yb 3+ . Below T N = 0.21 K, YbBi 2 ⁢IO 4 exhibits a stripe long-range magnetic order characterized by an ordering wave vector q m = (1/2, 0, 0) or its symmetry-equivalent (0, 1/2, 0), with magnetic moments aligned along q m . The ordered moment is approximately 79% of the classical prediction, significantly larger than expected from the isotropic J 1 -J 2 model, suggesting the possible involvement of exchange anisotropy in explaining this observation. We show that symmetry-allowed XXZ and bond-dependent anisotropic exchange terms in a square lattice can play a critical role in stabilizing the stripe order and suppressing the moment reduction as observed. These findings establish YbBi 2 ⁢ClO 4 and YbBi 2 ⁢IO 4 as unique platforms for exploring rich J eff = $\frac{1}{2}$ magnetism from two less investigated perspectives: (i) on a square lattice and (ii) within a (nearly) cubic ligand environment.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

Materials Data on ClO by Materials Project

ClO is Tetraauricupride structured and crystallizes in the cubic Pm-3m space group. The structure is zero-dimensional and consists of one hydrochloric acid molecule and one water molecule.

36 MATERIALS SCIENCE↗

Materials Data on ClO by Materials Project

ClO is alpha carbon monoxide-like structured and crystallizes in the tetragonal I4_1/amd space group. The structure is zero-dimensional and consists of eight chlorine molecules and eight hydrogen peroxide molecules.

36 MATERIALS SCIENCE↗

Magnetic excitations from the hexagonal spin clusters in the 𝑆 = $\frac{1}{2}$ distorted honeycomb lattice antiferromagnet Cu 2 ⁢(pymca)⁢ 3 ⁢(ClO 4 )

Cu 2 ⁢(pymca) ⁢3 (ClO 4 ) (pymca: pyrimidine-2-carboxylate) consists of a slightly distorted honeycomb lattice of Cu 2+ spins, which shows no long-range magnetic order down to 0.6 K. A magnetization study revealed 1/3 and 2/3 plateau phases [A. Okutani et al., J. Phys. Soc. Jpn. 88, 013703 (2019)], which is not expected for regular honeycomb antiferromagnets. Inelastic neutron scattering experiments were performed using a powder sample to investigate the exchange interactions of this material. The spin excitations from the singlet ground state to the first three triplet states, predicted from the antiferromagnetic hexagonal spin cluster interacting with 3.9 meV, were observed. Using the exact diagonalization methods, the intercluster coupling was estimated from the excitation peak width to be about 20% of the intracluster interaction, which is consistent with the previously reported value. Finally, our exchange path model explains the anisotropic exchange interactions in the distorted honeycomb plane.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

Materials Data on Hg3(ClO)2 by Materials Project

Hg3O2Cl2 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 6-coordinate geometry to three equivalent O2- and three equivalent Cl1- atoms. There are a spread of Hg–O bond distances ranging from 2.25–2.42 Å. There are a spread of Hg–Cl bond distances ranging from 2.71–3.26 Å. In the second Hg2+ site, Hg2+ is bonded in a distorted linear geometry to two equivalent O2- and four equivalent Cl1- atoms. Both Hg–O bond lengths are 2.11 Å. There are two shorter (3.07 Å) and two longer (3.08 Å) Hg–Cl bond lengths. O2- is bonded to four Hg2+ atoms to form a mixture of edge and corner-sharing OHg4 tetrahedra. Cl1- is bonded in a 5-coordinate geometry to five Hg2+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on Sr2Cu(ClO)2 by Materials Project

Sr2CuO2Cl2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Sr2+ is bonded in a 9-coordinate geometry to four equivalent O2- and five equivalent Cl1- atoms. All Sr–O bond lengths are 2.63 Å. There are four shorter (3.07 Å) and one longer (3.39 Å) Sr–Cl bond lengths. Cu2+ is bonded in a distorted square co-planar geometry to four equivalent O2- and two equivalent Cl1- atoms. All Cu–O bond lengths are 1.99 Å. Both Cu–Cl bond lengths are 2.93 Å. O2- is bonded to four equivalent Sr2+ and two equivalent Cu2+ atoms to form a mixture of corner, edge, and face-sharing OSr4Cu2 octahedra. The corner-sharing octahedral tilt angles are 0°. Cl1- is bonded in a 6-coordinate geometry to five equivalent Sr2+ and one Cu2+ atom.

36 MATERIALS SCIENCE↗

Materials Data on Ca2Cu(ClO)2 by Materials Project

Ca2CuO2Cl2 crystallizes in the tetragonal I4/mmm space group. The structure is three-dimensional. Ca2+ is bonded in a 9-coordinate geometry to four equivalent O2- and five equivalent Cl1- atoms. All Ca–O bond lengths are 2.51 Å. There are four shorter (3.00 Å) and one longer (3.27 Å) Ca–Cl bond lengths. Cu2+ is bonded in a distorted square co-planar geometry to four equivalent O2- and two equivalent Cl1- atoms. All Cu–O bond lengths are 1.94 Å. Both Cu–Cl bond lengths are 2.79 Å. O2- is bonded to four equivalent Ca2+ and two equivalent Cu2+ atoms to form a mixture of corner, edge, and face-sharing OCa4Cu2 octahedra. The corner-sharing octahedral tilt angles are 0°. Cl1- is bonded in a 6-coordinate geometry to five equivalent Ca2+ and one Cu2+ atom.

36 MATERIALS SCIENCE↗

Materials Data on H8PtN2(ClO)2 by Materials Project

PtN2H8(OCl)2 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of two azane;dichloroplatinum(2+);dihydrate molecules. Pt4+ is bonded in an octahedral geometry to two equivalent N3-, two equivalent O2-, and two equivalent Cl1- atoms. Both Pt–N bond lengths are 2.07 Å. Both Pt–O bond lengths are 2.05 Å. Both Pt–Cl bond lengths are 2.34 Å. N3- is bonded in a distorted trigonal non-coplanar geometry to one Pt4+ and three H1+ atoms. There are a spread of N–H bond distances ranging from 1.03–1.05 Å. There are four inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. O2- is bonded in a distorted single-bond geometry to one Pt4+ and one H1+ atom. Cl1- is bonded in a single-bond geometry to one Pt4+ atom.

36 MATERIALS SCIENCE↗

Materials Data on CuH4(ClO)2 by Materials Project

CuH4(OCl)2 crystallizes in the orthorhombic Pmna space group. The structure is zero-dimensional and consists of two 10125-13-0 molecules. Cu2+ is bonded in a distorted square co-planar geometry to two equivalent O2- and two equivalent Cl1- atoms. Both Cu–O bond lengths are 1.94 Å. Both Cu–Cl bond lengths are 2.29 Å. H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. O2- is bonded in a distorted trigonal planar geometry to one Cu2+ and two equivalent H1+ atoms. Cl1- is bonded in a distorted single-bond geometry to one Cu2+ atom.

36 MATERIALS SCIENCE↗

Materials Data on MgH4(ClO)2 by Materials Project

MgH4(OCl)2 crystallizes in the monoclinic C2/m space group. The structure is one-dimensional and consists of two MgH4(OCl)2 ribbons oriented in the (0, 0, 1) direction. Mg2+ is bonded to two equivalent O2- and four equivalent Cl1- atoms to form edge-sharing MgCl4O2 octahedra. Both Mg–O bond lengths are 2.04 Å. There are two shorter (2.53 Å) and two longer (2.59 Å) Mg–Cl bond lengths. H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. O2- is bonded in a distorted trigonal planar geometry to one Mg2+ and two equivalent H1+ atoms. Cl1- is bonded in an L-shaped geometry to two equivalent Mg2+ atoms.

36 MATERIALS SCIENCE↗

Materials Data on ZnH8C2N4(ClO)2 by Materials Project

ZnC2N4H8(OCl)2 is beta-like structured and crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two ZnC2N4H8(OCl)2 clusters. Zn2+ is bonded in a tetrahedral geometry to two O2- and two Cl1- atoms. There are one shorter (1.98 Å) and one longer (2.03 Å) Zn–O bond lengths. There are one shorter (2.24 Å) and one longer (2.26 Å) Zn–Cl bond lengths. There are two inequivalent C4+ sites. In the first C4+ site, C4+ is bonded in a trigonal planar geometry to two N3- and one O2- atom. There is one shorter (1.34 Å) and one longer (1.35 Å) C–N bond length. The C–O bond length is 1.28 Å. In the second C4+ site, C4+ is bonded in a trigonal planar geometry to two N3- and one O2- atom. There is one shorter (1.34 Å) and one longer (1.35 Å) C–N bond length. The C–O bond length is 1.29 Å. There are four inequivalent N3- sites. In the first N3- site, N3- is bonded in a trigonal planar geometry to one C4+ and two H1+ atoms. Both N–H bond lengths are 1.02 Å. In the second N3- site, N3- is bonded in a trigonal planar geometry to one C4+ and two H1+ atoms. Both N–H bond lengths are 1.02 Å. In the third N3- site, N3- is bonded in a trigonal planar geometry to one C4+ and two H1+ atoms. Both N–H bond lengths are 1.02 Å. In the fourth N3- site, N3- is bonded in a trigonal planar geometry to one C4+ and two H1+ atoms. Both N–H bond lengths are 1.02 Å. There are eight inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the second H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the third H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the fourth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the sixth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the seventh H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. In the eighth H1+ site, H1+ is bonded in a single-bond geometry to one N3- atom. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 120 degrees geometry to one Zn2+ and one C4+ atom. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to one Zn2+ and one C4+ atom. There are two inequivalent Cl1- sites. In the first Cl1- site, Cl1- is bonded in a single-bond geometry to one Zn2+ atom. In the second Cl1- site, Cl1- is bonded in a single-bond geometry to one Zn2+ atom.

36 MATERIALS SCIENCE↗

Materials Data on S(ClO)2 by Materials Project

SO2Cl2 is gamma plutonium structured and crystallizes in the orthorhombic Fdd2 space group. The structure is zero-dimensional and consists of eight sulfuryl chloride molecules. S6+ is bonded in a distorted tetrahedral geometry to two equivalent O2- and two equivalent Cl1- atoms. Both S–O bond lengths are 1.43 Å. Both S–Cl bond lengths are 2.03 Å. O2- is bonded in a single-bond geometry to one S6+ atom. Cl1- is bonded in a single-bond geometry to one S6+ atom.

36 MATERIALS SCIENCE↗

Materials Data on Cd3(ClO)2 by Materials Project

Cd3(OCl)2 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Cd2+ sites. In the first Cd2+ site, Cd2+ is bonded in a 5-coordinate geometry to three equivalent O2- and two equivalent Cl1- atoms. There are a spread of Cd–O bond distances ranging from 2.18–2.27 Å. There are one shorter (2.75 Å) and one longer (2.97 Å) Cd–Cl bond lengths. In the second Cd2+ site, Cd2+ is bonded to two equivalent O2- and four equivalent Cl1- atoms to form distorted corner-sharing CdCl4O2 octahedra. The corner-sharing octahedral tilt angles are 65°. Both Cd–O bond lengths are 2.16 Å. There are two shorter (2.80 Å) and two longer (2.91 Å) Cd–Cl bond lengths. O2- is bonded to four Cd2+ atoms to form a mixture of corner and edge-sharing OCd4 tetrahedra. Cl1- is bonded in a 4-coordinate geometry to four Cd2+ atoms.

36 MATERIALS SCIENCE↗