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Materials Data on Ba2Ho2Fe(CoO4)3 by Materials Project

Ba2Ho2Fe(CoO4)3 crystallizes in the tetragonal P4mm space group. The structure is three-dimensional. there are two inequivalent Ba2+ sites. In the first Ba2+ site, Ba2+ is bonded to twelve O2- atoms to form BaO12 cuboctahedra that share corners with four equivalent BaO12 cuboctahedra, corners with eight HoO12 cuboctahedra, faces with two HoO12 cuboctahedra, faces with four equivalent BaO12 cuboctahedra, faces with four equivalent FeO6 octahedra, and faces with four equivalent CoO6 octahedra. There are a spread of Ba–O bond distances ranging from 2.80–2.97 Å. In the second Ba2+ site, Ba2+ is bonded to twelve O2- atoms to form BaO12 cuboctahedra that share corners with four equivalent BaO12 cuboctahedra, corners with eight HoO12 cuboctahedra, faces with two HoO12 cuboctahedra, faces with four equivalent BaO12 cuboctahedra, and faces with eight CoO6 octahedra. There are a spread of Ba–O bond distances ranging from 2.80–2.92 Å. There are two inequivalent Ho3+ sites. In the first Ho3+ site, Ho3+ is bonded to twelve O2- atoms to form HoO12 cuboctahedra that share corners with four equivalent HoO12 cuboctahedra, corners with eight BaO12 cuboctahedra, faces with two BaO12 cuboctahedra, faces with four equivalent HoO12 cuboctahedra, and faces with eight CoO6 octahedra. There are eight shorter (2.56 Å) and four longer (2.80 Å) Ho–O bond lengths. In the second Ho3+ site, Ho3+ is bonded to twelve O2- atoms to form HoO12 cuboctahedra that share corners with four equivalent HoO12 cuboctahedra, corners with eight BaO12 cuboctahedra, faces with two BaO12 cuboctahedra, faces with four equivalent HoO12 cuboctahedra, faces with four equivalent FeO6 octahedra, and faces with four equivalent CoO6 octahedra. There are a spread of Ho–O bond distances ranging from 2.54–2.80 Å. Fe3+ is bonded to six O2- atoms to form FeO6 octahedra that share corners with two CoO6 octahedra, corners with four equivalent FeO6 octahedra, faces with four equivalent BaO12 cuboctahedra, and faces with four equivalent HoO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–12°. There are a spread of Fe–O bond distances ranging from 1.94–2.04 Å. There are three inequivalent Co+3.67+ sites. In the first Co+3.67+ site, Co+3.67+ is bonded to six O2- atoms to form CoO6 octahedra that share corners with six CoO6 octahedra, faces with four equivalent BaO12 cuboctahedra, and faces with four equivalent HoO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–11°. There are a spread of Co–O bond distances ranging from 1.84–2.00 Å. In the second Co+3.67+ site, Co+3.67+ is bonded to six O2- atoms to form CoO6 octahedra that share a cornercorner with one FeO6 octahedra, corners with five CoO6 octahedra, faces with four equivalent BaO12 cuboctahedra, and faces with four equivalent HoO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–12°. There are a spread of Co–O bond distances ranging from 1.79–1.99 Å. In the third Co+3.67+ site, Co+3.67+ is bonded to six O2- atoms to form CoO6 octahedra that share a cornercorner with one FeO6 octahedra, corners with five CoO6 octahedra, faces with four equivalent BaO12 cuboctahedra, and faces with four equivalent HoO12 cuboctahedra. The corner-sharing octahedra tilt angles range from 0–13°. There are a spread of Co–O bond distances ranging from 1.77–1.99 Å. There are eight inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to two equivalent Ba2+, two equivalent Ho3+, and two equivalent Fe3+ atoms. In the second O2- site, O2- is bonded in a 6-coordinate geometry to two equivalent Ba2+, two equivalent Ho3+, and two equivalent Co+3.67+ atoms. In the third O2- site, O2- is bonded in a 6-coordinate geometry to two equivalent Ba2+, two equivalent Ho3+, and two equivalent Co+3.67+ atoms. In the fourth O2- site, O2- is bonded in a 6-coordinate geometry to two equivalent Ba2+, two equivalent Ho3+, and two equivalent Co+3.67+ atoms. In the fifth O2- site, O2- is bonded to four equivalent Ba2+, one Fe3+, and one Co+3.67+ atom to form a mixture of distorted edge and corner-sharing OBa4FeCo octahedra. The corner-sharing octahedral tilt angles are 1°. In the sixth O2- site, O2- is bonded to four equivalent Ba2+ and two Co+3.67+ atoms to form a mixture of distorted edge and corner-sharing OBa4Co2 octahedra. The corner-sharing octahedral tilt angles are 2°. In the seventh O2- site, O2- is bonded in a linear geometry to four equivalent Ho3+ and two Co+3.67+ atoms. In the eighth O2- site, O2- is bonded in a linear geometry to four equivalent Ho3+, one Fe3+, and one Co+3.67+ atom.

36 MATERIALS SCIENCE↗

Materials Data on HoMn4(CuO4)3 by Materials Project

HoMn4(CuO4)3 crystallizes in the cubic Im-3 space group. The structure is three-dimensional. Ho3+ is bonded to twelve equivalent O2- atoms to form HoO12 cuboctahedra that share faces with eight equivalent MnO6 octahedra. All Ho–O bond lengths are 2.57 Å. Mn+4.50+ is bonded to six equivalent O2- atoms to form MnO6 octahedra that share corners with six equivalent MnO6 octahedra and faces with two equivalent HoO12 cuboctahedra. The corner-sharing octahedral tilt angles are 42°. All Mn–O bond lengths are 1.99 Å. Cu1+ is bonded in a square co-planar geometry to four equivalent O2- atoms. All Cu–O bond lengths are 1.94 Å. O2- is bonded in a 4-coordinate geometry to one Ho3+, two equivalent Mn+4.50+, and one Cu1+ atom.

36 MATERIALS SCIENCE↗

Materials Data on Ho2(SeO4)3 by Materials Project

Ho2(SeO4)3 crystallizes in the orthorhombic Pbcn space group. The structure is three-dimensional. Ho3+ is bonded to six O2- atoms to form HoO6 octahedra that share corners with six SeO4 tetrahedra. There are a spread of Ho–O bond distances ranging from 2.21–2.25 Å. There are two inequivalent Se6+ sites. In the first Se6+ site, Se6+ is bonded to four O2- atoms to form SeO4 tetrahedra that share corners with four equivalent HoO6 octahedra. The corner-sharing octahedra tilt angles range from 17–29°. All Se–O bond lengths are 1.66 Å. In the second Se6+ site, Se6+ is bonded to four O2- atoms to form SeO4 tetrahedra that share corners with four equivalent HoO6 octahedra. The corner-sharing octahedra tilt angles range from 4–38°. There is three shorter (1.66 Å) and one longer (1.67 Å) Se–O bond length. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a linear geometry to one Ho3+ and one Se6+ atom. In the second O2- site, O2- is bonded in a linear geometry to one Ho3+ and one Se6+ atom. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to one Ho3+ and one Se6+ atom. In the fourth O2- site, O2- is bonded in a bent 150 degrees geometry to one Ho3+ and one Se6+ atom. In the fifth O2- site, O2- is bonded in a bent 150 degrees geometry to one Ho3+ and one Se6+ atom. In the sixth O2- site, O2- is bonded in a bent 150 degrees geometry to one Ho3+ and one Se6+ atom.

36 MATERIALS SCIENCE↗

Materials Data on Ho2(WO4)3 by Materials Project

Ho2W3O12 crystallizes in the monoclinic P2_1/c space group. The structure is three-dimensional. there are two inequivalent Ho3+ sites. In the first Ho3+ site, Ho3+ is bonded to six O2- atoms to form HoO6 octahedra that share corners with six WO4 tetrahedra. There are a spread of Ho–O bond distances ranging from 2.23–2.27 Å. In the second Ho3+ site, Ho3+ is bonded to six O2- atoms to form HoO6 octahedra that share corners with six WO4 tetrahedra. There are a spread of Ho–O bond distances ranging from 2.22–2.28 Å. There are three inequivalent W6+ sites. In the first W6+ site, W6+ is bonded to four O2- atoms to form WO4 tetrahedra that share corners with four HoO6 octahedra. The corner-sharing octahedra tilt angles range from 12–34°. There is three shorter (1.81 Å) and one longer (1.82 Å) W–O bond length. In the second W6+ site, W6+ is bonded to four O2- atoms to form WO4 tetrahedra that share corners with four HoO6 octahedra. The corner-sharing octahedra tilt angles range from 7–35°. There is one shorter (1.81 Å) and three longer (1.82 Å) W–O bond length. In the third W6+ site, W6+ is bonded to four O2- atoms to form WO4 tetrahedra that share corners with four HoO6 octahedra. The corner-sharing octahedra tilt angles range from 11–35°. There is three shorter (1.81 Å) and one longer (1.82 Å) W–O bond length. There are twelve inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Ho3+ and one W6+ atom. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to one Ho3+ and one W6+ atom. In the third O2- site, O2- is bonded in a bent 150 degrees geometry to one Ho3+ and one W6+ atom. In the fourth O2- site, O2- is bonded in a bent 150 degrees geometry to one Ho3+ and one W6+ atom. In the fifth O2- site, O2- is bonded in a linear geometry to one Ho3+ and one W6+ atom. In the sixth O2- site, O2- is bonded in a bent 150 degrees geometry to one Ho3+ and one W6+ atom. In the seventh O2- site, O2- is bonded in a bent 150 degrees geometry to one Ho3+ and one W6+ atom. In the eighth O2- site, O2- is bonded in a linear geometry to one Ho3+ and one W6+ atom. In the ninth O2- site, O2- is bonded in a bent 150 degrees geometry to one Ho3+ and one W6+ atom. In the tenth O2- site, O2- is bonded in a bent 150 degrees geometry to one Ho3+ and one W6+ atom. In the eleventh O2- site, O2- is bonded in a linear geometry to one Ho3+ and one W6+ atom. In the twelfth O2- site, O2- is bonded in a linear geometry to one Ho3+ and one W6+ atom.

36 MATERIALS SCIENCE↗

High-accuracy first-principles-based rate coefficients for the reaction of OH and CH 3 OOH

Here, the ˙OH-initiated oxidation of methyl hydroperoxide, which plays an important role in the atmospheric chemistry of methane, was theoretically characterized using high-accuracy composite amHEAT-345(Q) coupled-cluster calculations followed by a two-dimensional E,J resolved master equation analysis. The reaction is found to proceed through two distinct hydrogen-bonded pre-reactive complexes leading to two product channels, in accord with the experimental observations: (i) ˙OH + CH 3 OOH → CH 3 OO˙ + H 2 O with a yield of 0.8 ± 0.1, and (ii) ˙OH + CH 3 OOH → HCHO + ˙OH + H 2 O with a yield of 0.2 ± 0.1. The calculated reaction enthalpies are within 0.2 kcal mol -1 of the benchmark ATcT values. Overall thermal rate coefficients obtained from first principles are found to be in the low-pressure limit at atmospheric pressure; the total rate coefficient can be expressed over the T = 200–450 K range as k(T) = 5.0 × 10 -12 × T -0.152 × exp(287/T) cm 3 s -1 , strongly supporting the experimental results of Vaghjiani and Ravishankara, with which this expression agrees within ca. 15%. The current results show that (i) is the principal reaction channel and support the view that, due to its inherently fast transformations, CH 3 OOH is an important redistribution species for HO x ˙ radicals in the Earth's atmosphere.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Effects of triaxiality and residual n p interaction in the proton emission from Ho 140

Here we present a detailed theoretical investigation of proton emission from 140 Ho within the nonadiabatic quasiparticle approach. The calculated proton emission half-life reproduces well the measured data. The importance of triaxiality and of the residual np interaction are studied. The ground state spin and parity of 139 Dy (daughter) and 140 Ho (parent) are ascertained unambiguously as 7/2 + and 3 – , respectively, by analyzing the rotational energies, half-lives, and branching ratios.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗

Kinetic study of reaction C 2 H 5 + HO 2 in a photolysis reactor with time-resolved Faraday rotation spectroscopy

The rate constant and branching ratios of ethyl reaction with hydroperoxyl radical, C 2 H 5 + HO 2 (1), a key radical-radical reaction for intermediate temperature combustion chemistry, were measured in situ for the first time in a photolysis Herriott cell by using mid-IR Faraday rotation spectroscopy (FRS) and UV-IR direct absorption spectroscopy (DAS). The microsecond time-resolved diagnostic technique in this work enabled the direct rate measurements of the target reaction at 40 and 80 mbar and reduced the experimental uncertainty considerably. C 2 H 5 and HO 2 radicals were generated by the photolysis of (COCl) 2 /C 2 H 5 I/CH 3 OH/O 2 /He mixture at 266 nm. By direct measurements of the transient profiles of C 2 H 5 , HO 2 and OH concentrations, the overall rate constant for this reaction at 297 K was determined as k 1 (40 mbar) = (3.8 ± 0.8) × 10 –11 cm 3 molecule –1 s –1 and k 1 (80 mbar) = (4.1 ± 1.0) × 10 –11 cm 3 molecule –1 s –1 . As a result, the direct observation of hydroxyl radical (OH) indicated that OH formation channel was the major channel with a branching ratio of 0.8 ± 0.1.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

Materials Data on Ho2(SO4)3 by Materials Project

Ho2(SO4)3 crystallizes in the trigonal R-3c space group. The structure is three-dimensional. Ho3+ is bonded to six O2- atoms to form HoO6 octahedra that share corners with six equivalent SO4 tetrahedra. There are three shorter (2.22 Å) and three longer (2.24 Å) Ho–O bond lengths. S6+ is bonded to four O2- atoms to form SO4 tetrahedra that share corners with four equivalent HoO6 octahedra. The corner-sharing octahedra tilt angles range from 23–26°. All S–O bond lengths are 1.48 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Ho3+ and one S6+ atom. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to one Ho3+ and one S6+ atom.

36 MATERIALS SCIENCE↗

Materials Data on Ho2(SeO4)3 by Materials Project

Ho2(SeO4)3 crystallizes in the trigonal R-3c space group. The structure is three-dimensional. Ho3+ is bonded to six O2- atoms to form HoO6 octahedra that share corners with six equivalent SeO4 tetrahedra. There are three shorter (2.23 Å) and three longer (2.24 Å) Ho–O bond lengths. Se6+ is bonded to four O2- atoms to form SeO4 tetrahedra that share corners with four equivalent HoO6 octahedra. The corner-sharing octahedra tilt angles range from 26–30°. All Se–O bond lengths are 1.66 Å. There are two inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 150 degrees geometry to one Ho3+ and one Se6+ atom. In the second O2- site, O2- is bonded in a bent 150 degrees geometry to one Ho3+ and one Se6+ atom.

36 MATERIALS SCIENCE↗

Studies of Low and Intermediate Temperature Oxidation of Propane up to 100 Atm in a Supercritical-Pressure Jet-Stirred Reactor

Here, the low and intermediate temperature oxidation of propane has been investigated by using a novel supercritical pressure jet stirred reactor (SP-JSR) with and without 20% CO 2 additions at fuel lean and rich conditions at 10 and 100 atm and 500–1000 K. The mole fractions of C 3 H 8 , O 2 , CO, CO 2 , CH 2 O, C 2 H 4 , CH 3 CHO, and C 3 H 6 were quantified by using a micro-gas chromatograph (µ-GC). The experiment showed that different from that of 10 atm, at 100 atm only a weak negative temperature coefficient (NTC) behavior was observed because of the significant shift of the intermediate temperature HO 2 chemistry to lower temperature. In addition, at 100 atm, existing models in literatures could successfully capture the onset temperatures of the low and intermediate chemistry, while under-predict the fuel oxidation quantitatively and fail to capture the NTC behavior between 650 and 780 K at both fuel lean and rich conditions. Similar discrepancy was observed in studies of n-butane and dimethyl ether (DME) oxidations in literatures, implying that there existed large uncertainties in hierarchy model development of fuels with low temperature chemistries at extremely high pressures. Reaction pathways and sensitivity analyses showed that RO 2 competing reactions through (P1) RO 2 = QOOH, (P2) RO 2 = C 3 H 6 + HO 2 , (P3) RO 2 + CH 2 O/HO 2 = RO 2 H + HCO / O 2 dominated the low and intermediate temperature chemistries, followed by HO 2 / H 2 O 2 chemistry at 100 atm, which differed from the dominant pathway through QOOH consumption reactions at lower pressures. Especially, P3 is a new pathway of RO 2 consumption at high pressures, which was not observed in importance at low pressures. Special attention should be paid to the accurate computations of n-C 3 H 7 O 2 / i-C 3 H 7 O 2 + CH 2 O and n-C 3 H 7 O 2 / i-C 3 H 7 O 2 + in the P3 pathway and n-C 3 H 7 O 2 / i-C 3 H 7 O 2 decomposition reactions in the P2 pathway at high pressures.

33 ADVANCED PROPULSION SYSTEMS↗

Structural and electronic properties of rare-earth chromites: A computational and experimental study

Here, in this work, the structural, optical, and electronic properties of rare-earth perovskites of the general formula R⁢ CrO 3 , where R⁢ represents the rare-earth Gd, Tb, Dy, Ho, Er, and Tm, have been studied in detail. These compounds were synthesized through a facile citrate route. X-ray diffraction, Raman spectroscopy, and UV-Visible spectroscopy were utilized to reveal the structural evolutions in R⁢ ⁢CrO 3 . The lattice parameters, Cr 3+ –O 2 –Cr 3+ bond angle, and CrO 6 octahedral distortions were found to strongly depend on the ionic radii of R⁢ . First-principles calculations based on density-functional theory within the generalized gradient approximation (GGA) of Perdew-Burke-Ernzerhof (PBE) and strongly constrained and appropriately normed (SCAN) meta-GGA were also employed to calculate the structural and electronic properties of R⁢ ⁢CrO 3 . The ground-state energy, lattice constants, electronic structures, and density of states of R⁢ ⁢CrO 3 were calculated. These provide some insights into the electronic characteristics of the R⁢ ⁢CrO 3 compounds. The calculated values of lattice parameters and band gaps with Hubbard U correction (SCAN+ U ) agree well with values measured experimentally and show more accuracy in predicting the ground-state crystal structure and band structure compared to PBE+ U approximation. The band gap of R⁢ ⁢CrO 3 is found to be independent of the ionic radii of R⁢ from both experiments and calculations.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

Materials Data on Li(HoS2)3 by Materials Project

HoLi(HoS2)2(S)2 crystallizes in the orthorhombic Cmmm space group. The structure is two-dimensional and consists of two holmium molecules; four hydrogen sulfide molecules; and one Li(HoS2)2 sheet oriented in the (0, 0, 1) direction. In the Li(HoS2)2 sheet, Li1+ is bonded in a distorted rectangular see-saw-like geometry to four equivalent S+1.67- atoms. All Li–S bond lengths are 2.47 Å. Ho3+ is bonded in a linear geometry to two equivalent S+1.67- atoms. Both Ho–S bond lengths are 2.51 Å. S+1.67- is bonded in a distorted linear geometry to one Li1+ and one Ho3+ atom.

36 MATERIALS SCIENCE↗

Materials Data on Ho2(NiB2)3 by Materials Project

Ho2(NiB2)3 crystallizes in the orthorhombic Cmmm space group. The structure is three-dimensional. Ho3+ is bonded in a 12-coordinate geometry to twelve B2- atoms. There are a spread of Ho–B bond distances ranging from 2.73–2.75 Å. There are two inequivalent Ni2+ sites. In the first Ni2+ site, Ni2+ is bonded in a distorted rectangular see-saw-like geometry to four equivalent B2- atoms. All Ni–B bond lengths are 2.23 Å. In the second Ni2+ site, Ni2+ is bonded in a 6-coordinate geometry to six B2- atoms. There are two shorter (2.13 Å) and four longer (2.17 Å) Ni–B bond lengths. There are two inequivalent B2- sites. In the first B2- site, B2- is bonded in a 9-coordinate geometry to four equivalent Ho3+, three Ni2+, and two B2- atoms. There is one shorter (1.74 Å) and one longer (1.75 Å) B–B bond length. In the second B2- site, B2- is bonded in a 9-coordinate geometry to four equivalent Ho3+, two equivalent Ni2+, and three B2- atoms. The B–B bond length is 1.74 Å.

36 MATERIALS SCIENCE↗

Materials Data on La(HoS2)3 by Materials Project

La(HoS2)3 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are three inequivalent Ho3+ sites. In the first Ho3+ site, Ho3+ is bonded to seven S2- atoms to form distorted HoS7 pentagonal bipyramids that share corners with three HoS6 octahedra, edges with two equivalent HoS6 octahedra, and edges with four equivalent HoS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 39–51°. There are a spread of Ho–S bond distances ranging from 2.70–2.93 Å. In the second Ho3+ site, Ho3+ is bonded to six S2- atoms to form HoS6 octahedra that share corners with three equivalent HoS6 octahedra, a cornercorner with one HoS7 pentagonal bipyramid, edges with four equivalent HoS6 octahedra, and edges with two equivalent HoS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 53–62°. There are a spread of Ho–S bond distances ranging from 2.68–2.78 Å. In the third Ho3+ site, Ho3+ is bonded to six S2- atoms to form HoS6 octahedra that share corners with three equivalent HoS6 octahedra, corners with two equivalent HoS7 pentagonal bipyramids, and edges with four equivalent HoS6 octahedra. The corner-sharing octahedra tilt angles range from 53–62°. There are a spread of Ho–S bond distances ranging from 2.66–2.80 Å. La3+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of La–S bond distances ranging from 2.94–3.08 Å. There are six inequivalent S2- sites. In the first S2- site, S2- is bonded in a 4-coordinate geometry to four Ho3+ atoms. In the second S2- site, S2- is bonded to three Ho3+ and one La3+ atom to form distorted SLaHo3 trigonal pyramids that share corners with two equivalent SLa2Ho3 square pyramids, corners with four SLa2Ho3 trigonal bipyramids, corners with two equivalent SLaHo3 trigonal pyramids, edges with three equivalent SLa2Ho3 square pyramids, and edges with two equivalent SLa3Ho2 trigonal bipyramids. In the third S2- site, S2- is bonded in a rectangular see-saw-like geometry to four Ho3+ atoms. In the fourth S2- site, S2- is bonded to three equivalent Ho3+ and two equivalent La3+ atoms to form distorted SLa2Ho3 square pyramids that share corners with six SLa2Ho3 trigonal bipyramids, corners with two equivalent SLaHo3 trigonal pyramids, edges with four equivalent SLa2Ho3 square pyramids, edges with two SLa2Ho3 trigonal bipyramids, and edges with three equivalent SLaHo3 trigonal pyramids. In the fifth S2- site, S2- is bonded to three Ho3+ and two equivalent La3+ atoms to form distorted SLa2Ho3 trigonal bipyramids that share corners with two equivalent SLa2Ho3 square pyramids, corners with two equivalent SLa3Ho2 trigonal bipyramids, corners with three equivalent SLaHo3 trigonal pyramids, an edgeedge with one SLa2Ho3 square pyramid, and edges with five SLa2Ho3 trigonal bipyramids. In the sixth S2- site, S2- is bonded to two equivalent Ho3+ and three equivalent La3+ atoms to form distorted SLa3Ho2 trigonal bipyramids that share corners with four equivalent SLa2Ho3 square pyramids, corners with two equivalent SLa2Ho3 trigonal bipyramids, a cornercorner with one SLaHo3 trigonal pyramid, an edgeedge with one SLa2Ho3 square pyramid, edges with seven SLa2Ho3 trigonal bipyramids, and edges with two equivalent SLaHo3 trigonal pyramids.

36 MATERIALS SCIENCE↗

Materials Data on Nd(HoS2)3 by Materials Project

Nd(HoS2)3 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are three inequivalent Ho3+ sites. In the first Ho3+ site, Ho3+ is bonded to seven S2- atoms to form distorted HoS7 pentagonal bipyramids that share corners with three HoS6 octahedra, edges with two equivalent HoS6 octahedra, and edges with four equivalent HoS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 38–51°. There are a spread of Ho–S bond distances ranging from 2.69–2.92 Å. In the second Ho3+ site, Ho3+ is bonded to six S2- atoms to form HoS6 octahedra that share corners with three equivalent HoS6 octahedra, a cornercorner with one HoS7 pentagonal bipyramid, edges with four equivalent HoS6 octahedra, and edges with two equivalent HoS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 57–60°. There are a spread of Ho–S bond distances ranging from 2.66–2.77 Å. In the third Ho3+ site, Ho3+ is bonded to six S2- atoms to form HoS6 octahedra that share corners with three equivalent HoS6 octahedra, corners with two equivalent HoS7 pentagonal bipyramids, and edges with four equivalent HoS6 octahedra. The corner-sharing octahedra tilt angles range from 57–60°. There are a spread of Ho–S bond distances ranging from 2.65–2.78 Å. Nd3+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of Nd–S bond distances ranging from 2.89–3.03 Å. There are six inequivalent S2- sites. In the first S2- site, S2- is bonded in a 4-coordinate geometry to four Ho3+ atoms. In the second S2- site, S2- is bonded to three Ho3+ and one Nd3+ atom to form distorted SNdHo3 trigonal pyramids that share corners with two equivalent SNd2Ho3 square pyramids, corners with four SNd2Ho3 trigonal bipyramids, corners with four SNdHo3 trigonal pyramids, edges with three equivalent SNd2Ho3 square pyramids, and edges with two equivalent SNd3Ho2 trigonal bipyramids. In the third S2- site, S2- is bonded to four Ho3+ atoms to form distorted SHo4 trigonal pyramids that share corners with three equivalent SNd2Ho3 square pyramids, corners with four equivalent SNd2Ho3 trigonal bipyramids, corners with four SNdHo3 trigonal pyramids, an edgeedge with one SNd2Ho3 trigonal bipyramid, and edges with two equivalent SHo4 trigonal pyramids. In the fourth S2- site, S2- is bonded to three equivalent Ho3+ and two equivalent Nd3+ atoms to form distorted SNd2Ho3 square pyramids that share corners with six SNd2Ho3 trigonal bipyramids, corners with five SNdHo3 trigonal pyramids, edges with four equivalent SNd2Ho3 square pyramids, edges with two SNd2Ho3 trigonal bipyramids, and edges with three equivalent SNdHo3 trigonal pyramids. In the fifth S2- site, S2- is bonded to three Ho3+ and two equivalent Nd3+ atoms to form distorted SNd2Ho3 trigonal bipyramids that share corners with two equivalent SNd2Ho3 square pyramids, corners with two equivalent SNd3Ho2 trigonal bipyramids, corners with seven SNdHo3 trigonal pyramids, an edgeedge with one SNd2Ho3 square pyramid, edges with five SNd2Ho3 trigonal bipyramids, and an edgeedge with one SHo4 trigonal pyramid. In the sixth S2- site, S2- is bonded to two equivalent Ho3+ and three equivalent Nd3+ atoms to form distorted SNd3Ho2 trigonal bipyramids that share corners with four equivalent SNd2Ho3 square pyramids, corners with two equivalent SNd2Ho3 trigonal bipyramids, a cornercorner with one SNdHo3 trigonal pyramid, an edgeedge with one SNd2Ho3 square pyramid, edges with seven SNd2Ho3 trigonal bipyramids, and edges with two equivalent SNdHo3 trigonal pyramids.

36 MATERIALS SCIENCE↗

Materials Data on Pr(HoS2)3 by Materials Project

Pr(HoS2)3 crystallizes in the monoclinic P2_1/m space group. The structure is three-dimensional. there are three inequivalent Ho3+ sites. In the first Ho3+ site, Ho3+ is bonded to seven S2- atoms to form distorted HoS7 pentagonal bipyramids that share corners with three HoS6 octahedra, edges with two equivalent HoS6 octahedra, and edges with four equivalent HoS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 38–51°. There are a spread of Ho–S bond distances ranging from 2.69–2.92 Å. In the second Ho3+ site, Ho3+ is bonded to six S2- atoms to form HoS6 octahedra that share corners with three equivalent HoS6 octahedra, a cornercorner with one HoS7 pentagonal bipyramid, edges with four equivalent HoS6 octahedra, and edges with two equivalent HoS7 pentagonal bipyramids. The corner-sharing octahedra tilt angles range from 55–61°. There are a spread of Ho–S bond distances ranging from 2.67–2.77 Å. In the third Ho3+ site, Ho3+ is bonded to six S2- atoms to form HoS6 octahedra that share corners with three equivalent HoS6 octahedra, corners with two equivalent HoS7 pentagonal bipyramids, and edges with four equivalent HoS6 octahedra. The corner-sharing octahedra tilt angles range from 55–61°. There are a spread of Ho–S bond distances ranging from 2.65–2.79 Å. Pr3+ is bonded in a 8-coordinate geometry to eight S2- atoms. There are a spread of Pr–S bond distances ranging from 2.91–3.05 Å. There are six inequivalent S2- sites. In the first S2- site, S2- is bonded in a 4-coordinate geometry to four Ho3+ atoms. In the second S2- site, S2- is bonded to three Ho3+ and one Pr3+ atom to form distorted SPrHo3 trigonal pyramids that share corners with two equivalent SPr2Ho3 square pyramids, corners with four SPr2Ho3 trigonal bipyramids, corners with two equivalent SPrHo3 trigonal pyramids, edges with three equivalent SPr2Ho3 square pyramids, and edges with two equivalent SPr3Ho2 trigonal bipyramids. In the third S2- site, S2- is bonded in a rectangular see-saw-like geometry to four Ho3+ atoms. In the fourth S2- site, S2- is bonded to three equivalent Ho3+ and two equivalent Pr3+ atoms to form distorted SPr2Ho3 square pyramids that share corners with six SPr2Ho3 trigonal bipyramids, corners with two equivalent SPrHo3 trigonal pyramids, edges with four equivalent SPr2Ho3 square pyramids, edges with two SPr2Ho3 trigonal bipyramids, and edges with three equivalent SPrHo3 trigonal pyramids. In the fifth S2- site, S2- is bonded to three Ho3+ and two equivalent Pr3+ atoms to form distorted SPr2Ho3 trigonal bipyramids that share corners with two equivalent SPr2Ho3 square pyramids, corners with two equivalent SPr3Ho2 trigonal bipyramids, corners with three equivalent SPrHo3 trigonal pyramids, an edgeedge with one SPr2Ho3 square pyramid, and edges with five SPr2Ho3 trigonal bipyramids. In the sixth S2- site, S2- is bonded to two equivalent Ho3+ and three equivalent Pr3+ atoms to form distorted SPr3Ho2 trigonal bipyramids that share corners with four equivalent SPr2Ho3 square pyramids, corners with two equivalent SPr2Ho3 trigonal bipyramids, a cornercorner with one SPrHo3 trigonal pyramid, an edgeedge with one SPr2Ho3 square pyramid, edges with seven SPr2Ho3 trigonal bipyramids, and edges with two equivalent SPrHo3 trigonal pyramids.

36 MATERIALS SCIENCE↗

Materials Data on Ho7C2I12N by Materials Project

Ho7C2NI12 crystallizes in the triclinic P-1 space group. The structure is three-dimensional. there are seven inequivalent Ho3+ sites. In the first Ho3+ site, Ho3+ is bonded to one C3- and five I1- atoms to form distorted HoCI5 octahedra that share corners with two HoC2I5 pentagonal bipyramids, an edgeedge with one HoCI5 octahedra, and edges with two HoC2I5 pentagonal bipyramids. The Ho–C bond length is 2.20 Å. There are a spread of Ho–I bond distances ranging from 2.96–3.33 Å. In the second Ho3+ site, Ho3+ is bonded to one C3- and five I1- atoms to form distorted HoCI5 octahedra that share an edgeedge with one HoCI5 octahedra and edges with two HoC2I5 pentagonal bipyramids. The Ho–C bond length is 2.19 Å. There are a spread of Ho–I bond distances ranging from 2.97–3.38 Å. In the third Ho3+ site, Ho3+ is bonded in a distorted single-bond geometry to two C3-, one N3-, and four I1- atoms. There are one shorter (2.59 Å) and one longer (2.62 Å) Ho–C bond lengths. The Ho–N bond length is 2.16 Å. There are a spread of Ho–I bond distances ranging from 3.06–3.24 Å. In the fourth Ho3+ site, Ho3+ is bonded in a distorted L-shaped geometry to two equivalent N3- and four I1- atoms. There are one shorter (2.18 Å) and one longer (2.19 Å) Ho–N bond lengths. There are a spread of Ho–I bond distances ranging from 3.29–3.37 Å. In the fifth Ho3+ site, Ho3+ is bonded to two C3- and five I1- atoms to form distorted HoC2I5 pentagonal bipyramids that share a cornercorner with one HoCI5 octahedra, a cornercorner with one HoC2I5 pentagonal bipyramid, edges with two HoCI5 octahedra, an edgeedge with one HoC2I5 pentagonal bipyramid, and a faceface with one HoC2I5 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 10°. There are one shorter (2.47 Å) and one longer (2.50 Å) Ho–C bond lengths. There are a spread of Ho–I bond distances ranging from 3.00–3.49 Å. In the sixth Ho3+ site, Ho3+ is bonded to two C3- and five I1- atoms to form distorted HoC2I5 pentagonal bipyramids that share a cornercorner with one HoCI5 octahedra, a cornercorner with one HoC2I5 pentagonal bipyramid, edges with two HoCI5 octahedra, an edgeedge with one HoC2I5 pentagonal bipyramid, and a faceface with one HoC2I5 pentagonal bipyramid. The corner-sharing octahedral tilt angles are 3°. There are one shorter (2.50 Å) and one longer (2.51 Å) Ho–C bond lengths. There are a spread of Ho–I bond distances ranging from 3.01–3.41 Å. In the seventh Ho3+ site, Ho3+ is bonded in a distorted single-bond geometry to two C3-, one N3-, and four I1- atoms. There are one shorter (2.61 Å) and one longer (2.62 Å) Ho–C bond lengths. The Ho–N bond length is 2.17 Å. There are a spread of Ho–I bond distances ranging from 3.09–3.25 Å. There are two inequivalent C3- sites. In the first C3- site, C3- is bonded in a 6-coordinate geometry to five Ho3+ and one C3- atom. The C–C bond length is 1.44 Å. In the second C3- site, C3- is bonded in a 6-coordinate geometry to five Ho3+ and one C3- atom. N3- is bonded to four Ho3+ atoms to form NHo4 tetrahedra that share a cornercorner with one IHo4 trigonal pyramid, an edgeedge with one NHo4 tetrahedra, and an edgeedge with one IHo4 trigonal pyramid. There are twelve inequivalent I1- sites. In the first I1- site, I1- is bonded in a 2-coordinate geometry to two Ho3+ atoms. In the second I1- site, I1- is bonded in a distorted bent 120 degrees geometry to two Ho3+ atoms. In the third I1- site, I1- is bonded in a 2-coordinate geometry to two Ho3+ atoms. In the fourth I1- site, I1- is bonded in a distorted T-shaped geometry to three Ho3+ atoms. In the fifth I1- site, I1- is bonded in a 3-coordinate geometry to three Ho3+ atoms. In the sixth I1- site, I1- is bonded in a distorted L-shaped geometry to two Ho3+ atoms. In the seventh I1- site, I1- is bonded in a 3-coordinate geometry to three Ho3+ atoms. In the eighth I1- site, I1- is bonded to four Ho3+ atoms to form distorted IHo4 trigonal pyramids that share a cornercorner with one NHo4 tetrahedra and an edgeedge with one NHo4 tetrahedra. In the ninth I1- site, I1- is bonded in a 3-coordinate geometry to three Ho3+ atoms. In the tenth I1- site, I1- is bonded in a distorted L-shaped geometry to two Ho3+ atoms. In the eleventh I1- site, I1- is bonded in a 3-coordinate geometry to three Ho3+ atoms. In the twelfth I1- site, I1- is bonded in a 3-coordinate geometry to three Ho3+ atoms.

36 MATERIALS SCIENCE↗

Study on ammonia and dimethyl ether oxidation and kinetic interaction up to 100 atm

NH 3 and DME dual fuel oxidation and kinetic coupling are experimentally studied by using a supercritical pressure jet-stirred reactor (SP-JSR) at 20 and 100 atm, over a temperature range of 500–900 K, and at fuel-lean and stoichiometric conditions with NH 3 to DME molar ratios of 4 and 0.62, respectively. An HP-Mech model for high-pressure NH3/DME oxidation is developed based on our previous studies and it shows generally better performance than other models in the literature on high-pressure oxidation experiments. Due to DME’s strong low-temperature reactivity, it dramatically enhances the oxidation of NH3 at low temperature. However, the effect of NH 3 on DME oxidation varies with temperature. At low temperatures, NH 3 inhibits low-temperature reactivity by consuming OH radicals. In addition, the NH 2 and NO x formation from NH 3 further suppresses the low-temperature DME reactivity by reducing alkylperoxyl and O 2 QOOH radicals via RO 2 + NH 2 = RO + H 2 NO, RO 2 + NO = RO + NO 2 and O 2 QOOH + NO = 2CH 2 O + HO 2 + NO 2 . At intermediate temperatures, due to enhanced kinetic coupling of NH 2 /NO x /HO 2 chemistry, DME oxidation is significantly promoted. It is found that there are two major NH 2 /NO x /HO 2 coupling pathways for OH radical production brought by NH 3 : (1) NH 2 + HO 2 = H 2 NO + OH and (2) NH 2 + NO 2 = H 2 NO + NO with NO + HO 2 = OH + NO 2 . Moreover, the resulting H 2 NO will further contribute to OH production via the H 2 NO/NO x /HONO coupling pathways: H 2 NO + NO 2 = HNO + HONO, HNO + NO 2 = HONO + NO, and HONO (+M) = OH + NO (+M). These new NH 2 /NO x /HO 2 and H 2 NO/NO x /HONO pathways play a critical role in promoting DME oxidation at intermediate temperatures. Novelty and Significance Statement: Blending NH 3 with DME can significantly enhance the reactivity of NH 3 and facilitate its practical application in advanced internal combustion engines. NH 3 /DME oxidation is studied in a novel supercritical pressure jet-stirred reactor up to 100 atm, a much higher pressure than previous studies. An interesting non-monotonic effect of NH3 addition on fuel oxidation has been found. Unique kinetic couplings of NH2/HO2/NOx and H2NO/NOx/HONO brough by NH3 and DME blending are identified to play important roles in radical generation and reactivity promotion. The valuable experimental data and key kinetics revealed in the current work can tremendously improve our understanding of NH 3 /DME oxidation via NO x /RO 2 and NH 2 / H 2 NO/HO 2 /NO x kinetic couplings at low to intermediate temperatures.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗