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At least 1,567 records · Page 87
All sourcesNASA NTRSDOE OSTI
NASA NTRS1995

ULF waves in the foreshock

We review our current knowledge of ULF waves in planetary foreshocks. Most of this knowledge comes from observations taken within a few Earth radii of the terrestrial bow shock. Terrestrial foreshock ULF waves can be divided into three types, large amplitude low frequency waves (approximately 30-s period), upstream propagating whistlers (1-Hz waves), and 3-s waves. The 30-s waves are apparently generated by back-streaming ion beams, while the 1-Hz waves are generated at the bow shock. The source of the 3-s waves has yet to be determined. In addition to issues concerning the source of ULF waves in the foreshock, the waves present a number of challenges, both in terms of data acquisition, and comparison with theory. The various waves have different coherence scales, from approximately 100 km to approximately 1 Earth radius. Thus multi-spacecraft separation strategies must be tailored to the phenomenon of interest. From a theoretical point of view, the ULF waves are observed in a plasma in which the thermal pressure is comparable to the magnetic pressure, and the rest-frame wave frequency can be moderate fraction of the proton gyro-frequency. This requires the use of kinetic plasma wave dispersion relations, rather than multi-fluid MHD. Lastly, and perhaps most significantly, ULF waves are used to probe the ambient plasma, with inferences being drawn concerning the types of energetic ion distributions within the foreshock. However, since most of the data were acquired close to the bow shock, the properties of the more distant foreshock have to be deduced mainly through extrapolation of the near-shock results. A general understanding of the wave and plasma populations within the foreshock, their interrelation, and evolution, requires additional data from the more distant foreshock.

Greenstadt, E. W.↗
DOE OSTI2012

ASSESSING THE FEASIBILITY OF COSMIC-RAY ACCELERATION BY MAGNETIC TURBULENCE AT THE GALACTIC CENTER

The presence of relativistic particles at the center of our Galaxy is evidenced by the diffuse TeV emission detected from the inner {approx}2 Degree-Sign of the Galaxy. Although it is not yet entirely clear whether the origin of the TeV photons is due to hadronic or leptonic interactions, the tight correlation of the intensity distribution with the distribution of molecular gas along the Galactic ridge strongly points to a pionic-decay process involving relativistic protons. In previous work, we concluded that point-source candidates, such as the supermassive black hole Sagittarius A* (identified with the High-Energy Stereoscopic System (HESS) source J1745-290) or the pulsar wind nebulae dispersed along the Galactic plane, could not account for the observed diffuse TeV emission from this region. Motivated by this result, we consider here the feasibility that the cosmic rays populating the Galactic center region are accelerated in situ by magnetic turbulence. Our results indicate that even in a highly conductive environment, this mechanism is efficient enough to energize protons within the intercloud medium to the {approx}>TeV energies required to produce the HESS emission.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2019

Hydrogen Effect on Electron-Phonon Interactions in L1{sub 0} FePd

The effect of H position in L1{sub 0}FePd magnetic equiatomic layered structure on electron-phonon interactions is studied via ab initio pseudopotentials density functional approach in the general gradient approximation. The structures investigated are L1{sub 0}FePd (parent structure), and the specific hydrides 2(FePd)1H (H@Fe layer) and 2(FePd)2H (H@Pd layer). At ground state (0 K), electronic band structure results demonstrate the emergence of Fermi surfaces (FS) in topologies of small isolated multipockets in the hydrides. Using the harmonic approximation I find the phonon energy dispersion of parent and H@Fe simple and classical but for H@Pd complex. I linked this latter structure to its topology of FS, known as Kohn anomaly. Using McMillan-Eliashberg model, I get superconducting transition temperature (T{sub c}) values ≈ 0.00 K, 3.48 K, and 19.75 K for the parent, H@Fe and H@Pd respectively. Therefore, these hypothetical hydrides prove that H position in the structure has a direct influence on T{sub c} values and consequently the suppression of magnetism.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2016

Comparison of catalytic activities for photocatalytic and sonocatalytic degradation of organic dye in the presence of ternary Fe{sub 3}O{sub 4}/ZnO/CuO magnetic heteregenous nanocatalyst

The Fe{sub 3}O{sub 4}/ZnO/CuO nanocatalyst with various CuO loading were synthesized by sol-gel method and were characterized by powder X-ray diffraction, field emission scanning electron microscopy, energy-dispersive X-ray spectroscopy, UV-Vis spectroscopy, and vibrating sample magnetometry. The findings demonstrate that all samples exhibit ferromagnetic behavior at room temperatureand containa well-crystalline ternary oxide nanocatalyst. Methylene blue was taken as the model of organic dye to evaluate its photocatalytic and sonocatalytic degradation in the presence of Fe{sub 3}O{sub 4}/ZnO/CuO nanocatalyst. The observed degradation activity indicate that the order of degradation of methylene blue issonocatalysis> photocatalysis. Fe{sub 3}O{sub 4}/ZnO/CuO nanocatalyst with the lowest CuO loading exhibit the highest rate of degradation of methylene blue during the sono- and photocatalytic processes. The experimental data shows that holes are the predominant oxidative species involved in the sono- and photodegradation of methylene blue.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2014

Numerical simulations of active region scale flux emergence: From spot formation to decay

We present numerical simulations of active region scale flux emergence covering a time span of up to 6 days. Flux emergence is driven by a bottom boundary condition that advects a semi-torus of magnetic field with 1.7 × 10{sup 22} Mx flux into the computational domain. The simulations show that, even in the absence of twist, the magnetic flux is able the rise through the upper 15.5 Mm of the convection zone and emerge into the photosphere to form spots. We find that spot formation is sensitive to the persistence of upflows at the bottom boundary footpoints, i.e., a continuing upflow would prevent spot formation. In addition, the presence of a torus-aligned flow (such flow into the retrograde direction is expected from angular momentum conservation during the rise of flux ropes through the convection zone) leads to a significant asymmetry between the pair of spots, with the spot corresponding to the leading spot on the Sun being more axisymmetric and coherent, but also forming with a delay relative to the following spot. The spot formation phase transitions directly into a decay phase. Subsurface flows fragment the magnetic field and lead to intrusions of almost field free plasma underneath the photosphere. When such intrusions reach photospheric layers, the spot fragments. The timescale for spot decay is comparable to the longest convective timescales present in the simulation domain. We find that the dispersal of flux from a simulated spot in the first two days of the decay phase is consistent with self-similar decay by turbulent diffusion.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2017

Fabrication of phosphonic acid films on nitinol nanoparticles by dynamic covalent assembly

Nitinol (NiTi) nanoparticles are a valuable metal alloy due to many unique properties that allow for medical applications. NiTi nanoparticles have the potential to form nanofluids, which can advance the thermal conductivity of fluids by controlling the surface functionalization through chemical attachment of organic acids to the surface to form self-assembled alkylphosphonate films. In this study, phosphonic functional head groups such as 16-phosphonohexadecanoic acid, octadecylphosphonic acid, and 12-aminododecylphosphonic acid were used to form an ordered and strongly chemically bounded film on the NiTi nanopowder. The surface of the NiTi nanoparticles was modified in order to tailor the chemical and physical properties to the desired application. The modified NiTi nanoparticles were characterized using infrared spectroscopy, powder X-ray diffraction, X-ray photoelectron spectroscopy, and 31 P solid-state nuclear magnetic resonance. The interfacial bonding was identified by spectroscopic data suggesting the phosphonic head group adsorbs in a mixed bidentate/monodentate binding motif on the NiTi nanoparticles. Dynamic light scattering and scanning electron microscopy-energy dispersive X-ray spectroscopy revealed the particle sizes. Differential scanning calorimetry was used to examine the phase transitions. Zeta potential determination as a function of pH was examined to investigate the surface properties of charged nanoparticles. In conclusion, the influence of environmental stability of the surface modifications was also assessed.

36 MATERIALS SCIENCE↗
DOE OSTI2017

Field induced spontaneous quasiparticle decay and renormalization of quasiparticle dispersion in a quantum antiferromagnet

The notion of a quasiparticle, such as a phonon, a roton or a magnon, is used in modern condensed matter physics to describe an elementary collective excitation. The intrinsic zero-temperature magnon damping in quantum spin systems can be driven by the interaction of the one-magnon states and multi-magnon continuum. However, detailed experimental studies on this quantum many-body effect induced by an applied magnetic field are rare. Here we present a high-resolution neutron scattering study in high fields on an S=1/2 antiferromagnet C 9 H 18 N 2 CuBr 4 . Finally, compared with the non-interacting linear spin–wave theory, our results demonstrate a variety of phenomena including field-induced renormalization of one-magnon dispersion, spontaneous magnon decay observed via intrinsic linewidth broadening, unusual non-Lorentzian two-peak structure in the excitation spectra and a dramatic shift of spectral weight from one-magnon state to the two-magnon continuum.

72 PHYSICS OF ELEMENTARY PARTICLES AND FIELDS↗
DOE OSTI2018

Dual oxidation state induced oxygen vacancies in Pr substituted BiFeO3 compounds: An effective material activation strategy to enhance the magnetic and visible light-driven photocatalytic properties

Highlights: • BiFeO{sub 3} with tunable oxygen vacancy is achieved through Pr substitution. • Dual oxidation of Pr ions is found to be the origin of oxygen vacancies in BiFeO{sub 3}. • Mechanism of the observed photocatalytic activity could be due to the oxygen vacancy. - Abstract: Bi{sub 1-x}P{sub x}FeO{sub 3} (BP{sub x}FO) nanoparticulates with tunable oxygen vacancy have been synthesized via sol-gel process. Substitution induced oxygen vacancy defects in BP{sub x}FO compositions were evidenced from their X-ray photoelectron spectra, where the mechanism behind the formation of oxygen vacancy was essentially found to be the dual oxidation states of Pr (+3/+4) ions. The origin of the observed enhanced magnetic properties in BP{sub x}FO nanoparticulates is attributed to be the oxygen vacancy mediated alterations in FeOFe bond angle and the alignment of Pr-3d magnetic moments with Fe-3d magnetic moments, which is resulted the ferromagnetic exchange interactions in the BP{sub x}FO system. The observed enhanced photocatalytic activity of BP{sub x}FO compositions is attributed to the formation of defective states in the valence band due to the oxygen vacancies that favored the dispersion of band edge position with required photocatalytic redox potential as well as the acceleration of the charge separation process in these defective BP{sub x}FO systems.

36 MATERIALS SCIENCE↗
DOE OSTI2015

Alfvén wave coupled with flow-driven fluid instability in interpenetrating plasmas

The Alfvén wave is analyzed in case of one quasineutral plasma propagating with some constant speed v{sub 0} through another static quasineutral plasma. A dispersion equation is derived describing the Alfvén wave coupled with the flow driven mode ω=kv{sub 0} and solutions are discussed analytically and numerically. The usual solutions for two oppositely propagating Alfvén waves are substantially modified due to the flowing plasma. More profound is modification of the solution propagating in the negative direction with respect to the magnetic field and the plasma flow. For a large enough flow speed (exceeding the Alfvén speed in the static plasma), this negative solution may become non-propagating, with frequency equal to zero. In this case, it represents a spatial variation of the electromagnetic field. For greater flow speed it becomes a forward mode, and it may merge with the positive one. This merging of the two modes represents the starting point for a flow-driven instability, with two complex-conjugate solutions. The Alfvén wave in interpenetrating plasmas is thus modified and coupled with the flow-driven mode and this coupled mode is shown to be growing when the flow speed is large enough. The energy for the instability is macroscopic kinetic energy of the flowing plasma. The dynamics of plasma particles caused by such a coupled wave still remains similar to the ordinary Alfvén wave. This means that well-known stochastic heating by the Alfvén wave may work, and this should additionally support the potential role of the Alfvén wave in the coronal heating.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2021

Magnetic ordering in the Ising antiferromagnetic pyrochlore Nd 2 ScNbO 7

The question of structural disorder and its effects on magnetism is relevant to a number of spin liquid candidate materials. Although commonly thought of as a route to spin glass behaviour, here we describe a system in which the structural disorder results in long-range antiferromagnetic order due to local symmetry breaking. Nd 2 ScNbO 7 is shown to have a dispersionless gapped excitation observed in other neodymium pyrochlores below T N = 0.37 K through polarized and inelastic neutron scattering. However the dispersing spin waves are not observed. This excited mode is shown to occur in only 14(2)% of the neodymium ions through spectroscopy and is consistent with total scattering measurements as well as the magnitude of the dynamic moment 0.26(2) μB . The remaining magnetic species order completely into the all-in all-out Ising antiferromagnetic structure. This can be seen as a result of local symmetry breaking due disordered Sc +3 and Nb +5 ions about the A-site. From this work, it has been established that B-site disorder restores the dipole-like behaviour of the Nd +3 ions compared to the Nd 2 ScNbO 7 parent series.

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEA↗
DOE OSTI2016

Planck intermediate results: XXXIII. Signature of the magnetic field geometry of interstellar filaments in dust polarization maps

Planck observations at 353 GHz provide the first fully sampled maps of the polarized dust emission towards interstellar filaments and their backgrounds (i.e., the emission observed in the surroundings of the filaments). The data allow us to determine the intrinsic polarization properties of the filaments and therefore to provide insight into the structure of their magnetic field (B). In this paper, we present the polarization maps of three nearby (several parsecs long) star-forming filaments of moderate column density (N H about 10 22 cm -2 ): Musca, B211, and L1506. These three filaments are detected above the background in dust total and polarized emission. We use the spatial information to separate Stokes I, Q, and U of the filaments from those of their backgrounds, an essential step in measuring the intrinsic polarization fraction (p) and angle (ψ) of each emission component. We find that the polarization angles in the three filaments (ψ fil ) are coherent along their lengths and not the same as in their backgrounds (ψ bg ). The differences between ψ fil and ψ bg are 12° and 54° for Musca and L1506, respectively, and only 6° in the case of B211. These differences forMusca and L1506 are larger than the dispersions of ψ, both along the filaments and in their backgrounds. The observed changes of ψ are direct evidence of variations of the orientation of the plane of the sky (POS) projection of the magnetic field. As in previous studies, we find a decrease of several per cent in p with N H from the backgrounds to the crest of the filaments. We show that the bulk of the drop in p within the filaments cannot be explained by random fluctuations of the orientation of the magnetic field because they are too small (σ ψ < 10°). We recognize the degeneracy between the dust alignment efficiency (by, e.g., radiative torques) and the structure of the B-field in causing variations in p, but we argue that the decrease in p from the backgrounds to the filaments results in part from depolarization associated with the 3D structure of the B-field: both its orientation in the POS and with respect to the POS. We do not resolve the inner structure of the filaments, but at the smallest scales accessible with Planck (~0.2 pc), the observed changes of ψ and p hold information on the magnetic field structure within filaments. Finally, they show that both the mean field and its fluctuations in the filaments are different from those of their backgrounds, which points to a coupling between the matter and the B-field in the filament formation process.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2018

WO x supported on γ-Al 2 O 3 with different morphologies as model catalysts for alkanol dehydration

The distinctive morphological and surface characteristics of platelet-like γ-Al2O3 were compared to a regular, commercial γ-Al2O3. γ-Al2O3 platelets display dominant (110) surface facets and higher densities of coordinative unsaturated penta-coordinate Al3+ (Al3+penta) sites than regular γ-Al2O3, as measured by solid-state magic-angle spinning nuclear magnetic resonance spectroscopy (MAS NMR). Such Al3+penta sites are also the preferred surface anchoring sites for tungsten oxide (WOx) species consistent with NMR analysis indicating that these sites are consumed upon WOx adsorption. The higher Al3+penta density on γ-Al2O3 platelets leads to greater WOx dispersion (or smaller WOx clusters), as demonstrated by scanning transmission electron microscopy and ultraviolet–visible spectroscopy, and WOx species at intermediate WOx surface concentration are the most active for the probe reaction of 2-butanol dehydration. WOx on γ-Al2O3 platelets approaches the highest turnover rates at higher surface densities than WOx on regular γ-Al2O3, yet with similar highest rate values for both series of catalysts. This indicates that different Al2O3 supports mainly affect the dispersion of supported WOx rather than the intrinsic reactivity of individual WOx clusters with similar size.

Environmental Molecular Sciences Laboratory↗
DOE OSTI2025

Anisotropic light-tailored RKKY interaction in two-dimensional 𝑑-wave altermagnets

Altermagnets are known in spintronics for their intrinsic spin-splitting and unconventional magnetic responses, particularly to magnetic impurities. However, effectively controlling the magnetic exchange interactions in altermagnets is challenging for practical applications. Here, in this work, we propose using circularly polarized light to tune the Ruderman-Kittel-Kasuya-Yosida (RKKY) interaction in two-dimensional 𝑑-wave altermagnets. Using the real-space retarded Green's functions approach, our results show that while the Heisenberg and Ising exchanges dominate, a notable Dzyaloshinskii–Moriya (DM) interaction also plays a key role. Furthermore, the inherent strength of altermagnetism imprints chirp-like signatures into the magnetic responses, which can be dynamically tuned via light. We mainly demonstrate that gate-induced Rashba spin-orbit coupling is essential in response to light—light selectively and anisotropically adjusts the DM interaction without affecting the other exchanges. Our findings further indicate that rotating the altermagnet by 45° relative to the light's polarization direction generates a Dirac-like dispersion and different DM interactions. We finally extract critical thresholds where light reverses DM interactions along one axis or balances both in-plane components. The anisotropic light-driven control of RKKY interactions in altermagnets not only highlights their unique properties but also opens new avenues for engineering tailored magnetic characteristics in spintronic applications.

altermagnetism↗
DOE OSTI2020

Self-consistent theory of the Darrieus–Landau and Rayleigh–Taylor instabilities with self-generated magnetic fields

The Rayleigh–Taylor (RT) and Darrieus–Landau (DL) instabilities are studied in an inertial confinement fusion context within the framework of small critical-to-shell density ratio D R and weak acceleration regime, i.e., large Froude number Fr. The quasi-isobaric analysis in Sanz et al. is completed with the inclusion of non-isobaric and self-generated magnetic-field effects. The analysis is restricted to perturbation wavelengths k~1 larger than the conduction length scale at the ablation front, yet its validity ranges from wavelengths shorter and larger than the conduction layer width (distance between the ablation front and the critical surface). The use of a sharp boundary model leads to a single analytical expression of the dispersion relation encompassing both instabilities. The two new effects come into play by modifying the perturbed mass and momentum fluxes at the ablation front. The momentum flux (perturbed pressure at the spike) is the predominant stabilizing mechanism in the RT instability (overpressure) and the driving mechanism in the DL instability (underpressure). The non-isobaric effects notably modify the scaling laws in the DL limit, leading to an underpressure scaling as ~k –11/15 rather than ~k –2/5 obtained in the quasi-isobaric model. The magnetic fields are generated due to misalignment between pressure and density gradients (Biermann battery effect). They affect the hydrodynamics by bending the heat flux lines. Within the framework of this paper, they enhance ablation, resulting in a stabilizing effect that peaks for perturbation wavelengths comparable to the conduction layer width. Here, the combination of parameters D R Fr 2/3 defines the region of predominance of each instability in the dispersion relation. It is proven that the DL region falls outside of the parameter range in inertial confinement fusion.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2023

Multiresonant metasurfaces for arbitrarily broad bandwidth pulse chirping and dispersion compensation

Here, we show that ultrathin metasurfaces with a specific multiresonant response can enable simultaneously arbitrarily strong and arbitrarily broadband dispersion compensation, pulse (de)chirping, and compression or broadening. This breakthrough overcomes the fundamental limitations of both conventional nonresonant approaches (bulky) and modern singly resonant metasurfaces (narrowband) for quadratic phase manipulations of electromagnetic signals. The required nonuniform trains of resonances in the electric and magnetic sheet conductivities that completely control phase delay, group delay, and chirp are rigorously derived and the limitations imposed by fundamental physical constraints are thoroughly discussed. Subsequently, a practical, truncated approximation by finite sequences of physically realizable linear resonances is constructed and the associated error is quantified. By appropriate spectral ordering of the resonances, operation can be achieved either in transmission or reflection mode, enabling full space coverage. The proposed concept is not limited to dispersion compensation, but introduces a generic and powerful ultrathin platform for the spatiotemporal control of broadband real-world signals with a myriad of applications in modern optics, microwave photonics, radar, and communication systems.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2011

MASS AND MAGNETIC DISTRIBUTIONS IN SELF-GRAVITATING SUPER-ALFVENIC TURBULENCE WITH ADAPTIVE MESH REFINEMENT

In this work, we present the mass and magnetic distributions found in a recent adaptive mesh refinement magnetohydrodynamic simulation of supersonic, super-Alfvenic, self-gravitating turbulence. Power-law tails are found in both mass density and magnetic field probability density functions, with P({rho}) {proportional_to} {rho}{sup -1.6} and P(B) {proportional_to} B{sup -2.7}. A power-law relationship is also found between magnetic field strength and density, with B {proportional_to} {rho}{sup 0.5}, throughout the collapsing gas. The mass distribution of gravitationally bound cores is shown to be in excellent agreement with recent observation of prestellar cores. The mass-to-flux distribution of cores is also found to be in excellent agreement with recent Zeeman splitting measurements. We also compare the relationship between velocity dispersion and density to the same cores, and find an increasing relationship between the two, with {sigma} {proportional_to} n{sup 0.25}, also in agreement with the observations. We then estimate the potential effects of ambipolar diffusion in our cores and find that due to the weakness of the magnetic field in our simulation, the inclusion of ambipolar diffusion in our simulation will not cause significant alterations of the flow dynamics.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2014

Reducing the ordering temperature of CoPt nanoparticles by B additive

We reported the effect of boron addition on magnetic properties and structure of CoPt nanoparticles prepared by a polyol method. The magnetic property measurement showed that the CoPt-B sample exhibited a much larger coercivity compared to the sample without B additive at the same annealing temperature. Transmission electron microscopy and energy dispersive X-ray spectroscopy revealed that the average particle size was about 2 nm for the as-synthesized sample with the ratio of Co and Pt close to 1:1. After annealing, the particle sizes increased but the composition was maintained. The phase transformation of the nanoparticles versus temperature was investigated using a combination of X-ray diffraction and in-situ X-ray absorption analysis. It was shown that the phase transition temperature at which the nanoparticles change from the disordered A1 phase to the ordered L1{sub 0} phase occurs at temperature of 600 °C. We concluded that boron additives could reduce the ordering temperature of CoPt of about 100 °C.

71 CLASSICAL AND QUANTUM MECHANICS, GENERAL PHYSIC↗
DOE OSTI2016

Ce{sub 11}Ge{sub 3.73(2)}In{sub 6.27}: Solid-state synthesis, crystal structure and site-preference

A novel intermetallic compound of Ce{sub 11}Ge{sub 3.73(2)}In{sub 6.27} has been synthesized through the high-temperature solid-state reaction using Nb-ampoules. A batch of well grown block-/short bar-shaped single-crystals has been obtained, and the crystal structure of the title compound has been characterized by single-crystal X-ray diffraction analyses. Ce{sub 11}Ge{sub 3.73(2)}In{sub 6.27} adopts the Ho{sub 11}Ge{sub 10}-type structure belonging to the tetragonal space group I4/mmm (Z=4, Pearson symbol tI84) with nine crystallographically unique atomic positions in the asymmetric unit. The lattice parameters are a=12.0163(1) Å and c=16.5396(2) Å. The overall crystal structure can simply be depicted as an assembly of three different types of co-facial cationic polyhedra centered by anions, which is further enclosed by the three-dimensional (3-D) cage-like anionic framework. The extra amount of In is observed in one of three isolated anionic sites resulting in introducing the Ge/In-mixed site at the Wyckoff 4e site. This unique site-preference of In substitution for Ge at the 4e site has been enlightened via the atomic size-aspect which was fully supported and rationalized by the site- and bond-energies analyses using tight-binding linear muffin-tin orbital (TB-LMTO) calculations. Energy-dispersive X-ray spectroscopy (EDS), density of states (DOS), crystal orbital Hamilton population (COHP), and electron localization function (ELF) analyses for the title compound are also presented. Magnetic susceptibility measurement proves that an antiferromagnetic ordering of Ce atoms at a low temperature with a paramagnetic Curie temperature of −23.2 K. - Graphical abstract: Reported is experimental and theoretical investigations for Ce{sub 11}Ge{sub 3.73(2)}In{sub 6.27}, which is the first reported example having the extra amounts of In substitution for Ge at one of three “isolated” anionic sites in the Ho{sub 11}Ge{sub 10}-type phase. The observed In site-preference toward the particular anionic site was rationalized via the atomic size-aspect supported by comprehensive analyses for the site-energies including the Wyckoff 4e and 8j sites. - Highlights: • Block or short-bar shaped single-crystals of Ce{sub 11}Ge{sub 3.73(2)}In{sub 6.27} were synthesized. • The first example of having the In/Ge mixture at the “isolated” anionic site. • The site-preference of In was rationalized by the site- and bond-energies.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗