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All sourcesNASA NTRSDOE OSTI
DOE OSTI2020

Polarizabilities of neutral atoms and atomic ions with a noble gas electron configuration

Atomic polarizabilities play an important role in the development of force fields for molecular simulations, as well as for the development of qualitative concepts of atomic and molecular behavior. Coupled cluster theory at the coupled cluster singles doubles triples level with very large correlation-consistent basis sets with extended diffuse functions has been used to predict the polarizabilities of the atomic neutrals, mono-cations and mono-anions with a noble gas configuration. Additional corrections for scalar relativistic and spin–orbit effects were also included for the electron configurations of Kr, Xe, and Rn. The results are in excellent agreement with experiment or with other high level calculations where available. The current results for most of these species represent the best available values for the polarizabilities. The results show that the polarizability of H - is very difficult to calculate without extremely diffuse functions. The polarizability of H - is the largest value, 34.05 Å 3 , calculated for all species in the current study. The polarizabilities of the remaining halogen anions are also the best available values. The polarizabilities of the halogen anions (excluding F - ) and H - have a linear correlation with the electron affinity of the neutral atom. Spin– orbit effects, even for closed shell species, cannot be ignored for quantitative accuracy, and the inclusion of spin–orbit effects for Fr + , Rn, and At - increases the polarizability by 4%, 6%, and 15%, respectively.

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

Materials Data on H2Os3(CO)10 by Materials Project

H2Os3(CO)10 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two Os(CO)4 clusters and two OsH(CO)3 clusters. In each Os(CO)4 cluster, Os2- is bonded in a distorted see-saw-like geometry to four C+2.40+ atoms. There is two shorter (1.92 Å) and two longer (1.95 Å) Os–C bond length. There are four inequivalent C+2.40+ sites. In the first C+2.40+ site, C+2.40+ is bonded in a distorted linear geometry to one Os2- and one O2- atom. The C–O bond length is 1.16 Å. In the second C+2.40+ site, C+2.40+ is bonded in a linear geometry to one Os2- and one O2- atom. The C–O bond length is 1.16 Å. In the third C+2.40+ site, C+2.40+ is bonded in a distorted linear geometry to one Os2- and one O2- atom. The C–O bond length is 1.16 Å. In the fourth C+2.40+ site, C+2.40+ is bonded in a linear geometry to one Os2- and one O2- atom. The C–O bond length is 1.16 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom. In each OsH(CO)3 cluster, there are two inequivalent Os2- sites. In the first Os2- site, Os2- is bonded to three C+2.40+ and two H1+ atoms to form distorted edge-sharing OsH2C3 square pyramids. There is two shorter (1.90 Å) and one longer (1.93 Å) Os–C bond length. Both Os–H bond lengths are 1.86 Å. In the second Os2- site, Os2- is bonded to three C+2.40+ and two H1+ atoms to form distorted edge-sharing OsH2C3 square pyramids. There are a spread of Os–C bond distances ranging from 1.90–1.92 Å. There is one shorter (1.85 Å) and one longer (1.86 Å) Os–H bond length. There are six inequivalent C+2.40+ sites. In the first C+2.40+ site, C+2.40+ is bonded in a distorted linear geometry to one Os2- and one O2- atom. The C–O bond length is 1.16 Å. In the second C+2.40+ site, C+2.40+ is bonded in a linear geometry to one Os2- and one O2- atom. The C–O bond length is 1.16 Å. In the third C+2.40+ site, C+2.40+ is bonded in a linear geometry to one Os2- and one O2- atom. The C–O bond length is 1.16 Å. In the fourth C+2.40+ site, C+2.40+ is bonded in a linear geometry to one Os2- and one O2- atom. The C–O bond length is 1.16 Å. In the fifth C+2.40+ site, C+2.40+ is bonded in a linear geometry to one Os2- and one O2- atom. The C–O bond length is 1.16 Å. In the sixth C+2.40+ site, C+2.40+ is bonded in a linear geometry to one Os2- and one O2- atom. The C–O bond length is 1.16 Å. There are two inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in an L-shaped geometry to two Os2- atoms. In the second H1+ site, H1+ is bonded in an L-shaped geometry to two Os2- atoms. There are six inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom. In the fifth O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom. In the sixth O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PN3OF2 by Materials Project

F2PNNNO crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of four F2PNNNO clusters. In two of the F2PNNNO clusters, P5+ is bonded in a tetrahedral geometry to one N+0.33-, one O2-, and two F1- atoms. The P–N bond length is 1.66 Å. The P–O bond length is 1.46 Å. Both P–F bond lengths are 1.56 Å. There are three inequivalent N+0.33- sites. In the first N+0.33- site, N+0.33- is bonded in a distorted bent 120 degrees geometry to one P5+ and one N+0.33- atom. The N–N bond length is 1.24 Å. In the second N+0.33- site, N+0.33- is bonded in a linear geometry to two N+0.33- atoms. The N–N bond length is 1.14 Å. In the third N+0.33- site, N+0.33- is bonded in a single-bond geometry to one N+0.33- atom. O2- is bonded in a single-bond geometry to one P5+ atom. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one P5+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one P5+ atom. In two of the F2PNNNO clusters, P5+ is bonded in a distorted tetrahedral geometry to one N+0.33-, one O2-, and two F1- atoms. The P–N bond length is 1.66 Å. The P–O bond length is 1.46 Å. Both P–F bond lengths are 1.56 Å. There are three inequivalent N+0.33- sites. In the first N+0.33- site, N+0.33- is bonded in a 2-coordinate geometry to one P5+ and one N+0.33- atom. The N–N bond length is 1.24 Å. In the second N+0.33- site, N+0.33- is bonded in a linear geometry to two N+0.33- atoms. The N–N bond length is 1.14 Å. In the third N+0.33- site, N+0.33- is bonded in a single-bond geometry to one N+0.33- atom. O2- is bonded in a single-bond geometry to one P5+ atom. There are two inequivalent F1- sites. In the first F1- site, F1- is bonded in a single-bond geometry to one P5+ atom. In the second F1- site, F1- is bonded in a single-bond geometry to one P5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on VH14SO11 by Materials Project

V(H2O)6H2OSO4 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four sulfuric acid molecules, four water molecules, and four V(H2O)6 clusters. In two of the V(H2O)6 clusters, V2+ is bonded in an octahedral geometry to six O2- atoms. There are a spread of V–O bond distances ranging from 2.16–2.19 Å. There are six inequivalent H1+ sites. In the first 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 second 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 third 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 fourth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the fifth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 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. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted water-like geometry to one V2+ and two H1+ atoms. In the second O2- site, O2- is bonded in a distorted water-like geometry to one V2+ and two H1+ atoms. In the third O2- site, O2- is bonded in a distorted water-like geometry to one V2+ and two H1+ atoms. In two of the V(H2O)6 clusters, V2+ is bonded in an octahedral geometry to six O2- atoms. There are four shorter (2.16 Å) and two longer (2.23 Å) V–O bond lengths. There are six inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a distorted single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the second H1+ site, H1+ is bonded in a distorted single-bond geometry to one O2- atom. The H–O bond length is 1.00 Å. In the third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 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. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted water-like geometry to one V2+ and two H1+ atoms. In the second O2- site, O2- is bonded in a distorted water-like geometry to one V2+ and two H1+ atoms. In the third O2- site, O2- is bonded in a distorted water-like geometry to one V2+ and two H1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on ReH3O5 by Materials Project

H(ReO4)H2O crystallizes in the triclinic P1 space group. The structure is zero-dimensional and consists of two H(ReO4)H2O clusters. In one of the H(ReO4)H2O clusters, Re7+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of Re–O bond distances ranging from 1.73–1.82 Å. There are three inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the third H1+ site, H1+ is bonded in a linear geometry to two O2- atoms. There is one shorter (1.12 Å) and one longer (1.32 Å) H–O bond length. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted trigonal non-coplanar geometry to three H1+ atoms. In the second O2- site, O2- is bonded in a single-bond geometry to one Re7+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one Re7+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Re7+ and one H1+ atom. In the fifth O2- site, O2- is bonded in a single-bond geometry to one Re7+ atom. In one of the H(ReO4)H2O clusters, Re7+ is bonded in a tetrahedral geometry to four O2- atoms. There are a spread of Re–O bond distances ranging from 1.74–1.79 Å. There are three inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the third H1+ site, H1+ is bonded in a linear geometry to two O2- atoms. There is one shorter (1.16 Å) and one longer (1.22 Å) H–O bond length. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a trigonal planar geometry to three H1+ atoms. In the second O2- site, O2- is bonded in a single-bond geometry to one Re7+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one Re7+ atom. In the fourth O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Re7+ and one H1+ atom. In the fifth O2- site, O2- is bonded in a single-bond geometry to one Re7+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Li2P7(H3N)9 by Materials Project

(Li(NH3)4)2(P)7NH3 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two ammonia molecules, fourteen phosphine molecules, and four Li(NH3)4 clusters. In two of the Li(NH3)4 clusters, Li1+ is bonded in a tetrahedral geometry to four N3- atoms. There are a spread of Li–N bond distances ranging from 2.07–2.09 Å. There are four inequivalent N3- sites. In the first N3- site, N3- is bonded to one Li1+ and three H+0.78+ atoms to form distorted corner-sharing NLiH3 tetrahedra. There is one shorter (1.02 Å) and two longer (1.03 Å) N–H bond length. In the second N3- site, N3- is bonded to one Li1+ and three H+0.78+ atoms to form distorted corner-sharing NLiH3 tetrahedra. There is one shorter (1.02 Å) and two longer (1.03 Å) N–H bond length. In the third N3- site, N3- is bonded to one Li1+ and three H+0.78+ atoms to form distorted corner-sharing NLiH3 tetrahedra. There is two shorter (1.02 Å) and one longer (1.03 Å) N–H bond length. In the fourth N3- site, N3- is bonded to one Li1+ and three H+0.78+ atoms to form distorted corner-sharing NLiH3 tetrahedra. There is one shorter (1.02 Å) and two longer (1.03 Å) N–H bond length. There are twelve inequivalent H+0.78+ sites. In the first H+0.78+ site, H+0.78+ is bonded in a single-bond geometry to one N3- atom. In the second H+0.78+ site, H+0.78+ is bonded in a single-bond geometry to one N3- atom. In the third H+0.78+ site, H+0.78+ is bonded in a single-bond geometry to one N3- atom. In the fourth H+0.78+ site, H+0.78+ is bonded in a single-bond geometry to one N3- atom. In the fifth H+0.78+ site, H+0.78+ is bonded in a single-bond geometry to one N3- atom. In the sixth H+0.78+ site, H+0.78+ is bonded in a single-bond geometry to one N3- atom. In the seventh H+0.78+ site, H+0.78+ is bonded in a single-bond geometry to one N3- atom. In the eighth H+0.78+ site, H+0.78+ is bonded in a single-bond geometry to one N3- atom. In the ninth H+0.78+ site, H+0.78+ is bonded in a single-bond geometry to one N3- atom. In the tenth H+0.78+ site, H+0.78+ is bonded in a single-bond geometry to one N3- atom. In the eleventh H+0.78+ site, H+0.78+ is bonded in a single-bond geometry to one N3- atom. In the twelfth H+0.78+ site, H+0.78+ is bonded in a single-bond geometry to one N3- atom. In two of the Li(NH3)4 clusters, Li1+ is bonded in a tetrahedral geometry to four N3- atoms. There are two shorter (2.06 Å) and two longer (2.08 Å) Li–N bond lengths. There are four inequivalent N3- sites. In the first N3- site, N3- is bonded to one Li1+ and three H+0.78+ atoms to form distorted corner-sharing NLiH3 tetrahedra. There is one shorter (1.02 Å) and two longer (1.03 Å) N–H bond length. In the second N3- site, N3- is bonded to one Li1+ and three H+0.78+ atoms to form distorted corner-sharing NLiH3 tetrahedra. There is two shorter (1.02 Å) and one longer (1.03 Å) N–H bond length. In the third N3- site, N3- is bonded to one Li1+ and three H+0.78+ atoms to form distorted corner-sharing NLiH3 tetrahedra. There is two shorter (1.02 Å) and one longer (1.03 Å) N–H bond length. In the fourth N3- site, N3- is bonded to one Li1+ and three H+0.78+ atoms to form distorted corner-sharing NLiH3 tetrahedra. There is two shorter (1.02 Å) and one longer (1.03 Å) N–H bond length. There are twelve inequivalent H+0.78+ sites. In the first H+0.78+ site, H+0.78+ is bonded in a single-bond geometry to one N3- atom. In the second H+0.78+ site, H+0.78+ is bonded in a single-bond geometry to one N3- atom. In the third H+0.78+ site, H+0.78+ is bonded in a single-bond geometry to one N3- atom. In the fourth H+0.78+ site, H+0.78+ is bonded in a single-bond geometry to one N3- atom. In the fifth H+0.78+ site, H+0.78+ is bonded in a single-bond geometry to one N3- atom. In the sixth H+0.78+ site, H+0.78+ is bonded in a single-bond geometry to one N3- atom. In the seventh H+0.78+ site, H+0.78+ is bonded in a single-bond geometry to one N3- atom. In the eighth H+0.78+ site, H+0.78+ is bonded in a single-bond geometry to one N3- atom. In the ninth H+0.78+ site, H+0.78+ is bonded in a single-bond geometry to one N3- atom. In the tenth H+0.78+ site, H+0.78+ is bonded in a single-bond geometry to one N3- atom. In the eleventh H+0.78+ site, H+0.78+ is bonded in a single-bond geometry to one N3- atom. In the twelfth H+0.78+ site, H+0.78+ is bonded in a single-bond geometry to one N3- atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on NiH8(NO5)2 by Materials Project

NiH8(NO5)2 crystallizes in the triclinic P-1 space group. The structure is zero-dimensional and consists of two NiH8(NO5)2 clusters. In one of the NiH8(NO5)2 clusters, Ni2+ is bonded in an octahedral geometry to six O2- atoms. There are a spread of Ni–O bond distances ranging from 2.06–2.13 Å. N5+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of N–O bond distances ranging from 1.25–1.30 Å. There are four inequivalent H1+ sites. In the first 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 second 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 third H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 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. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted water-like geometry to one Ni2+ and two H1+ atoms. In the second O2- site, O2- is bonded in a distorted water-like geometry to one Ni2+ and two H1+ atoms. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to one Ni2+ and one N5+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one N5+ atom. In the fifth O2- site, O2- is bonded in a single-bond geometry to one N5+ atom. In one of the NiH8(NO5)2 clusters, Ni2+ is bonded in an octahedral geometry to six O2- atoms. There are four shorter (2.08 Å) and two longer (2.12 Å) Ni–O bond lengths. N5+ is bonded in a trigonal planar geometry to three O2- atoms. There is two shorter (1.25 Å) and one longer (1.30 Å) N–O bond length. There are four inequivalent H1+ sites. In the first 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 second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. In the third 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 fourth H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.98 Å. There are five inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted water-like geometry to one Ni2+ and two H1+ atoms. In the second O2- site, O2- is bonded in a distorted water-like geometry to one Ni2+ and two H1+ atoms. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to one Ni2+ and one N5+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one N5+ atom. In the fifth O2- site, O2- is bonded in a single-bond geometry to one N5+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on MnH4(C2O3)2 by Materials Project

MnH4(C2O3)2 crystallizes in the monoclinic C2/c space group. The structure is zero-dimensional and consists of twelve MnH4(C2O3)2 clusters. In four of the MnH4(C2O3)2 clusters, Mn2+ is bonded in an octahedral geometry to six O2- atoms. There are two shorter (2.17 Å) and four longer (2.22 Å) Mn–O bond lengths. There are two inequivalent C+1.50+ sites. In the first C+1.50+ site, C+1.50+ is bonded in a single-bond geometry to one O2- atom. The C–O bond length is 1.26 Å. In the second C+1.50+ site, C+1.50+ is bonded in a single-bond geometry to one O2- atom. The C–O bond length is 1.26 Å. There are two inequivalent H1+ sites. In the first 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 second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a 2-coordinate geometry to one Mn2+ and one C+1.50+ atom. In the second O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Mn2+ and one C+1.50+ atom. In the third O2- site, O2- is bonded in a distorted water-like geometry to one Mn2+ and two H1+ atoms. In eight of the MnH4(C2O3)2 clusters, Mn2+ is bonded in an octahedral geometry to six O2- atoms. There are a spread of Mn–O bond distances ranging from 2.17–2.24 Å. There are two inequivalent C+1.50+ sites. In the first C+1.50+ site, C+1.50+ is bonded in a single-bond geometry to one O2- atom. The C–O bond length is 1.26 Å. In the second C+1.50+ site, C+1.50+ is bonded in a single-bond geometry to one O2- atom. The C–O bond length is 1.26 Å. There are two inequivalent H1+ sites. In the first 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 second H1+ site, H1+ is bonded in a single-bond geometry to one O2- atom. The H–O bond length is 0.99 Å. There are three inequivalent O2- sites. In the first O2- site, O2- is bonded in a distorted bent 150 degrees geometry to one Mn2+ and one C+1.50+ atom. In the second O2- site, O2- is bonded in a 2-coordinate geometry to one Mn2+ and one C+1.50+ atom. In the third O2- site, O2- is bonded in a distorted water-like geometry to one Mn2+ and two H1+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2022

Surface Fe clusters promote syngas reaction to oxygenates on Rh catalysts modified by atomic layer deposition

Converting syngas to higher oxygenates is a promising strategy for sustainably producing fuels and chemicals used every day. Rh-based catalysts promoted with metal oxides have long been of interest for oxygenate synthesis, but the role of promoters and the structure of the catalyst during reaction are often not well understood. In this work, we characterize a Rh/SiO 2 catalyst modified by Fe 2 O 3 deposited by atomic layer deposition (ALD). Here, we show that Fe 2 O 3 deposits selectively on the Rh nanoparticles and enhances both the turnover frequency and the oxygenate selectivity of the catalysts. A maximum 29% selectivity towards higher oxygenates is achieved with just 1 cycle of Fe 2 O 3 ALD, and we relate the trends in selectivity to the changing availability of surface sites that drive higher alcohol (e.g., ethanol and propanol) formation. Further, we show that the ALD promoter mitigates catalyst sintering, improving the stability of these materials. In-situ X-ray absorption spectroscopy experiments reveal that the Fe 2 O 3 undergoes reduction during the catalyst pretreatment and forms Fe clusters on the surface of the Rh that migrate but remain stable under syngas reaction conditions. We find that modification of the Rh with these surface Fe species is key to the enhanced alcohol production observed in these materials.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2025

The importance of accounting for the Tolman correction to surface tension for nucleation and growth modeling of Fe clusters

Gibbs free energies of clusters are required for predictive modeling of cluster growth during condensation of a cooling vapor. Here, we present a straightforward method of calculating free energies of cluster formation using the data from molecular dynamics (MD) simulations. We apply this method to iron clusters having from 2 to 100 atoms. The energies obtained are verified by comparing to an MD-simulated equilibrium cluster size distribution in a sub-saturated vapor. We show that these free energies differ significantly from those obtained with a commonly used spherical cluster approximation, which relies on a surface tension coefficient of a flat surface, as it is used in the classical nucleation theory (CNT). We show that the spherical cluster approximation in CNT can be improved by using a cluster-size-dependent Tolman correction for the surface tension. The Tolman length and effective surface tension values were derived for iron clusters, and they significantly differ from the commonly used experimentally measured values. This improved approximation does not account for geometric magic number effects responsible for spikes and troughs in densities of neighbor cluster sizes. Nonetheless, it allows to more accurately model cluster formation from a cooling vapor. It better reproduces the condensation timeline, overall shape of the cluster size distribution, average cluster size, and the distribution width. In contrast, using a constant surface tension coefficient (as done in CNT) resulted in incorrect condensation dynamics and cluster size distributions. The analytical expression for cluster nucleation rate from CNT was updated to account for the size-dependence of cluster surface tension.

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

Structure and dynamics of $\mathrm{Fe_{90}}$$\mathrm{Si_3}$$\mathrm{O_7}$ liquids close to Earth's liquid core conditions

Using an artificial neural-network machine learning interatomic potential, we have performed molecular dynamics simulations to study the structure and dynamics of $\mathrm{Fe_{90}}$$\mathrm{Si_3}$$\mathrm{O_7}$ liquid close to the Earth's liquid core conditions. Here, the simulation results reveal that the short-range structural order (SRO) in the $\mathrm{Fe_{90}}$$\mathrm{Si_3}$$\mathrm{O_7}$ liquid is very strong. About 80% of the atoms are arranged in crystallinelike SRO motifs. In particular, ~ $70$% of Fe-centered clusters can be classified as either hexagonal-close-packed-like or icosahedrallike SRO motifs. The SRO clusters centered on Fe, Si, or O atoms are strongly intermixed and homogenously distributed throughout the liquid. The atomic structure of the liquid and the fractions of dominant SRO clusters are not sensitive to pressure/temperature used in the simulations except that the SRO of the O-centered clusters is enhanced close to inner core pressures. The O-diffusion coefficient is about two to three times larger than the Fe and Si ions and increases more rapidly in the deeper core regions.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2020

Materials Data on Be4N6O19 by Materials Project

Be4N6O19 crystallizes in the trigonal P3 space group. The structure is zero-dimensional and consists of three Be4N6O19 clusters. In one of the Be4N6O19 clusters, there are two inequivalent Be2+ sites. In the first Be2+ site, Be2+ is bonded to four O2- atoms to form corner-sharing BeO4 tetrahedra. There is one shorter (1.63 Å) and three longer (1.64 Å) Be–O bond length. In the second Be2+ site, Be2+ is bonded to four O2- atoms to form corner-sharing BeO4 tetrahedra. There are a spread of Be–O bond distances ranging from 1.63–1.65 Å. There are two inequivalent N5+ sites. In the first N5+ site, N5+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of N–O bond distances ranging from 1.21–1.31 Å. In the second N5+ site, N5+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.21 Å) and two longer (1.30 Å) N–O bond length. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one N5+ atom. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to one Be2+ and one N5+ atom. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to one Be2+ and one N5+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one N5+ atom. In the fifth O2- site, O2- is bonded in a bent 120 degrees geometry to one Be2+ and one N5+ atom. In the sixth O2- site, O2- is bonded in a bent 120 degrees geometry to one Be2+ and one N5+ atom. In the seventh O2- site, O2- is bonded in a tetrahedral geometry to four Be2+ atoms. In two of the Be4N6O19 clusters, there are two inequivalent Be2+ sites. In the first Be2+ site, Be2+ is bonded to four O2- atoms to form corner-sharing BeO4 tetrahedra. There is one shorter (1.63 Å) and three longer (1.64 Å) Be–O bond length. In the second Be2+ site, Be2+ is bonded to four O2- atoms to form corner-sharing BeO4 tetrahedra. There are a spread of Be–O bond distances ranging from 1.63–1.65 Å. There are two inequivalent N5+ sites. In the first N5+ site, N5+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of N–O bond distances ranging from 1.21–1.31 Å. In the second N5+ site, N5+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.21 Å) and two longer (1.30 Å) N–O bond length. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a bent 120 degrees geometry to one Be2+ and one N5+ atom. In the second O2- site, O2- is bonded in a bent 120 degrees geometry to one Be2+ and one N5+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one N5+ atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to one Be2+ and one N5+ atom. In the fifth O2- site, O2- is bonded in a bent 120 degrees geometry to one Be2+ and one N5+ atom. In the sixth O2- site, O2- is bonded in a single-bond geometry to one N5+ atom. In the seventh O2- site, O2- is bonded in a tetrahedral geometry to four Be2+ atoms.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on Mg4N6O19 by Materials Project

Mg4N6O19 crystallizes in the trigonal P3 space group. The structure is zero-dimensional and consists of three Mg4N6O19 clusters. In one of the Mg4N6O19 clusters, there are two inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to four O2- atoms to form corner-sharing MgO4 tetrahedra. There are a spread of Mg–O bond distances ranging from 1.97–2.01 Å. In the second Mg2+ site, Mg2+ is bonded to four O2- atoms to form corner-sharing MgO4 tetrahedra. There is one shorter (1.94 Å) and three longer (2.01 Å) Mg–O bond length. There are two inequivalent N5+ sites. In the first N5+ site, N5+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.22 Å) and two longer (1.30 Å) N–O bond length. In the second N5+ site, N5+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of N–O bond distances ranging from 1.21–1.30 Å. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one N5+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one N5+ atom. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to one Mg2+ and one N5+ atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to one Mg2+ and one N5+ atom. In the fifth O2- site, O2- is bonded in a bent 120 degrees geometry to one Mg2+ and one N5+ atom. In the sixth O2- site, O2- is bonded in a bent 120 degrees geometry to one Mg2+ and one N5+ atom. In the seventh O2- site, O2- is bonded in a tetrahedral geometry to four Mg2+ atoms. In two of the Mg4N6O19 clusters, there are two inequivalent Mg2+ sites. In the first Mg2+ site, Mg2+ is bonded to four O2- atoms to form corner-sharing MgO4 tetrahedra. There is one shorter (1.95 Å) and three longer (1.99 Å) Mg–O bond length. In the second Mg2+ site, Mg2+ is bonded to four O2- atoms to form corner-sharing MgO4 tetrahedra. There is one shorter (1.95 Å) and three longer (1.99 Å) Mg–O bond length. There are two inequivalent N5+ sites. In the first N5+ site, N5+ is bonded in a trigonal planar geometry to three O2- atoms. There are a spread of N–O bond distances ranging from 1.21–1.30 Å. In the second N5+ site, N5+ is bonded in a trigonal planar geometry to three O2- atoms. There is one shorter (1.21 Å) and two longer (1.30 Å) N–O bond length. There are seven inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one N5+ atom. In the second O2- site, O2- is bonded in a tetrahedral geometry to four Mg2+ atoms. In the third O2- site, O2- is bonded in a bent 120 degrees geometry to one Mg2+ and one N5+ atom. In the fourth O2- site, O2- is bonded in a bent 120 degrees geometry to one Mg2+ and one N5+ atom. In the fifth O2- site, O2- is bonded in a single-bond geometry to one N5+ atom. In the sixth O2- site, O2- is bonded in a bent 120 degrees geometry to one Mg2+ and one N5+ atom. In the seventh O2- site, O2- is bonded in a bent 120 degrees geometry to one Mg2+ and one N5+ atom.

36 MATERIALS SCIENCE↗
NASA NTRS1960

On Ion Clusters in the Interstellar Gas

In a recent paper V.I. Krassovsky (1958) predicts the occurrence of clusters of large numbers of atoms and molecules around ions in the interstellar gas. He then proposes a number of physicochemical processes that would be considerably enhanced by the high particle density in such clusters. In particular, he suggests that absorption by negative ions formed in the clusters would account for the interstellar extinction without any necessity for the presence of grains. Because of the important consequences that ion clusters could have, it is necessary to examine their occurrence more fully. This note re-examines the formation of ion clusters in space and shows that even ion-molecule pairs are essentially non-existent. Ion clusters have been considered by Bloom and Margenau (1952) from the same point of view as that used by Krassovsky, whose basic reference (Joffe and Semenov 1933) unfortunately is not available. A different approach has been used by Eyring, Hirschfelder, and Taylor (1936) following the methods of chemical equilibrium. Both the references cited here enable one to conclude that clustering is negligible. Therefore, the treatment of Eyring et al. is more appropriate than the method of Bloom and Margenau, which depends on the statistical equilibrium of an atmosphere in a force field.

Donn, Bertram↗
DOE OSTI2020

Materials Data on H2Os4Pt(CO)15 by Materials Project

Os3PtH2(CO)11Os(CO)4 crystallizes in the monoclinic P2_1/c space group. The structure is zero-dimensional and consists of four Os(CO)4 clusters and four Os3PtH2(CO)11 clusters. In each Os(CO)4 cluster, Os+1.50- is bonded in a rectangular see-saw-like geometry to four C+2.40+ atoms. There are a spread of Os–C bond distances ranging from 1.90–1.95 Å. There are four inequivalent C+2.40+ sites. In the first C+2.40+ site, C+2.40+ is bonded in a distorted linear geometry to one Os+1.50- and one O2- atom. The C–O bond length is 1.16 Å. In the second C+2.40+ site, C+2.40+ is bonded in a distorted linear geometry to one Os+1.50- and one O2- atom. The C–O bond length is 1.16 Å. In the third C+2.40+ site, C+2.40+ is bonded in a linear geometry to one Os+1.50- and one O2- atom. The C–O bond length is 1.16 Å. In the fourth C+2.40+ site, C+2.40+ is bonded in a linear geometry to one Os+1.50- and one O2- atom. The C–O bond length is 1.17 Å. There are four inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom. In each Os3PtH2(CO)11 cluster, there are three inequivalent Os+1.50- sites. In the first Os+1.50- site, Os+1.50- is bonded in a 4-coordinate geometry to three C+2.40+ and one H1+ atom. There are a spread of Os–C bond distances ranging from 1.90–1.92 Å. The Os–H bond length is 1.86 Å. In the second Os+1.50- site, Os+1.50- is bonded in a 4-coordinate geometry to three C+2.40+ and one H1+ atom. There is one shorter (1.90 Å) and two longer (1.91 Å) Os–C bond length. The Os–H bond length is 1.86 Å. In the third Os+1.50- site, Os+1.50- is bonded in a 6-coordinate geometry to one Pt2-, three C+2.40+, and two H1+ atoms. The Os–Pt bond length is 2.76 Å. There is two shorter (1.91 Å) and one longer (1.92 Å) Os–C bond length. There is one shorter (1.81 Å) and one longer (1.82 Å) Os–H bond length. Pt2- is bonded in a distorted water-like geometry to one Os+1.50- and two C+2.40+ atoms. There is one shorter (1.91 Å) and one longer (1.92 Å) Pt–C bond length. There are eleven inequivalent C+2.40+ sites. In the first C+2.40+ site, C+2.40+ is bonded in a distorted linear geometry to one Pt2- and one O2- atom. The C–O bond length is 1.16 Å. In the second C+2.40+ site, C+2.40+ is bonded in a distorted linear geometry to one Pt2- and one O2- atom. The C–O bond length is 1.16 Å. In the third C+2.40+ site, C+2.40+ is bonded in a distorted linear geometry to one Os+1.50- and one O2- atom. The C–O bond length is 1.17 Å. In the fourth C+2.40+ site, C+2.40+ is bonded in a distorted linear geometry to one Os+1.50- and one O2- atom. The C–O bond length is 1.17 Å. In the fifth C+2.40+ site, C+2.40+ is bonded in a linear geometry to one Os+1.50- and one O2- atom. The C–O bond length is 1.17 Å. In the sixth C+2.40+ site, C+2.40+ is bonded in a distorted linear geometry to one Os+1.50- and one O2- atom. The C–O bond length is 1.17 Å. In the seventh C+2.40+ site, C+2.40+ is bonded in a distorted linear geometry to one Os+1.50- and one O2- atom. The C–O bond length is 1.16 Å. In the eighth C+2.40+ site, C+2.40+ is bonded in a distorted linear geometry to one Os+1.50- and one O2- atom. The C–O bond length is 1.16 Å. In the ninth C+2.40+ site, C+2.40+ is bonded in a linear geometry to one Os+1.50- and one O2- atom. The C–O bond length is 1.16 Å. In the tenth C+2.40+ site, C+2.40+ is bonded in a linear geometry to one Os+1.50- and one O2- atom. The C–O bond length is 1.16 Å. In the eleventh C+2.40+ site, C+2.40+ is bonded in a linear geometry to one Os+1.50- and one O2- atom. The C–O bond length is 1.16 Å. There are two inequivalent H1+ sites. In the first H1+ site, H1+ is bonded in a bent 120 degrees geometry to two Os+1.50- atoms. In the second H1+ site, H1+ is bonded in a water-like geometry to two Os+1.50- atoms. There are eleven inequivalent O2- sites. In the first O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom. In the second O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom. In the third O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom. In the fourth O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom. In the fifth O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom. In the sixth O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom. In the seventh O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom. In the eighth O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom. In the ninth O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom. In the tenth O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom. In the eleventh O2- site, O2- is bonded in a single-bond geometry to one C+2.40+ atom.

36 MATERIALS SCIENCE↗
DOE OSTI2024

New insights into the mechanism of ultrasonic atomization for the production of metal powders in additive manufacturing

Ultrasonic atomization is one of the promising technologies for producing metal powders for additive manufacturing, where precise control of particle size and morphology is essential. In this study, we coupled an ultrasonic transducer with a carbon fiber plate and atomized liquid droplets and films under different vibration amplitudes. Water, glycerol, and pure aluminum melt were used to study the atomization mechanism and the resulting droplet/powder characteristics, respectively. High-speed optical and ultrafast synchrotron X-ray imaging were used to study in situ the ultrasonic atomization dynamics, including pulsation and clustering of cavities inside the liquid layer/films, development of capillary waves, and formation of liquid droplets. For the first time, we observed and captured the occurrence of cavitation during the atomization of resting drops, films and impact droplets. The inertial cavitation events interfered with the capillary waves across the interphase boundary, puncturing and breaking the boundary to produce atomized mist. The in situ observation revealed the intricate dynamics of ultrasonic atomization and underscored the pivotal role of cavitation events throughout the entire atomization process. We also conducted experiments on ultrasonic atomization of liquid aluminum, producing particles of perfectly spherical shape. The particle size tended to decrease with reduced vibration amplitude Our work has demonstrated the important processing strategies on how to tailor the particle size while ensuring consistent particle shape and morphology, which is the key processing capability for producing high quality powders for additive manufacturing applications.

36 MATERIALS SCIENCE↗
DOE OSTI2020

Materials Data on PtBr3N2 by Materials Project

Pt(NBr)2Pt(NBr2)2 is Protactinium structured and crystallizes in the orthorhombic Pmmn space group. The structure is zero-dimensional and consists of two Pt(NBr)2 clusters and two Pt(NBr2)2 clusters. In each Pt(NBr)2 cluster, Pt5+ is bonded in a rectangular see-saw-like geometry to two equivalent N1- and two equivalent Br1- atoms. Both Pt–N bond lengths are 1.79 Å. Both Pt–Br bond lengths are 2.49 Å. N1- is bonded in a single-bond geometry to one Pt5+ atom. Br1- is bonded in a single-bond geometry to one Pt5+ atom. In each Pt(NBr2)2 cluster, Pt5+ is bonded in an octahedral geometry to two equivalent N1- and four Br1- atoms. Both Pt–N bond lengths are 2.03 Å. All Pt–Br bond lengths are 2.47 Å. N1- is bonded in a single-bond geometry to one Pt5+ atom. There are three inequivalent Br1- sites. In the first Br1- site, Br1- is bonded in a single-bond geometry to one Pt5+ atom. In the second Br1- site, Br1- is bonded in a single-bond geometry to one Pt5+ atom. In the third Br1- site, Br1- is bonded in a single-bond geometry to one Pt5+ atom.

36 MATERIALS SCIENCE↗