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DOE OSTI2020

Materials Data on Y(Al10Cr)2 by Materials Project

Al20Cr2Y crystallizes in the cubic Fd-3m space group. The structure is three-dimensional. Y is bonded in a 4-coordinate geometry to sixteen Al atoms. There are four shorter (3.12 Å) and twelve longer (3.21 Å) Y–Al bond lengths. Cr is bonded to twelve Al atoms to form CrAl12 cuboctahedra that share corners with six equivalent CrAl12 cuboctahedra, edges with eighteen equivalent AlYAl10Cr cuboctahedra, and faces with six equivalent AlYAl10Cr cuboctahedra. There are six shorter (2.56 Å) and six longer (2.78 Å) Cr–Al bond lengths. There are three inequivalent Al sites. In the first Al site, Al is bonded in a 12-coordinate geometry to two equivalent Cr and ten Al atoms. There are a spread of Al–Al bond distances ranging from 2.70–2.82 Å. In the second Al site, Al is bonded in a distorted linear geometry to two equivalent Y and twelve equivalent Al atoms. All Al–Al bond lengths are 3.09 Å. In the third Al site, Al is bonded to one Y, one Cr, and ten Al atoms to form distorted AlYAl10Cr cuboctahedra that share corners with fifteen equivalent AlYAl10Cr cuboctahedra, edges with two equivalent AlYAl10Cr cuboctahedra, edges with three equivalent CrAl12 cuboctahedra, a faceface with one CrAl12 cuboctahedra, and faces with fifteen equivalent AlYAl10Cr cuboctahedra. There are a spread of Al–Al bond distances ranging from 2.72–2.90 Å.

36 MATERIALS SCIENCE↗

DOE OSTI2020

Materials Data on Y(VSn)6 by Materials Project

YV6Sn6 crystallizes in the hexagonal P6/mmm space group. The structure is three-dimensional. Y is bonded to eight Sn atoms to form edge-sharing YSn8 hexagonal bipyramids. There are two shorter (3.06 Å) and six longer (3.19 Å) Y–Sn bond lengths. V is bonded in a 12-coordinate geometry to six Sn atoms. There are a spread of V–Sn bond distances ranging from 2.80–2.86 Å. There are three inequivalent Sn sites. In the first Sn site, Sn is bonded in a 8-coordinate geometry to one Y, six equivalent V, and one Sn atom. The Sn–Sn bond length is 3.11 Å. In the second Sn site, Sn is bonded in a 6-coordinate geometry to six equivalent V atoms. In the third Sn site, Sn is bonded in a 12-coordinate geometry to three equivalent Y and six equivalent V atoms.

36 MATERIALS SCIENCE↗

DOE OSTI2022

Acetone to isobutene conversion on Zn x Ti y O z : Effects of TiO 2 facet

In this study, liquid-phase chemical grafting method was used to graft Zn onto TiO 2 with preferentially exposed (1 0 1) or (0 0 1) facet. The obtained Zn x Ti y O z materials were characterized using various techniques (e.g., XRD, Raman, DRIFTS etc.) and evaluated for the acetone-to-isobutene reaction. It was found that over TiO 2 (0 0 1), both terminal and bridging hydroxyls were readily titrated by Zn deposition, whereas a substantial amount of bridging hydroxyls on TiO 2 (1 0 1) remained. Although dominant Zn-O-terminated surface was obtained on two Zn x Ti y O z samples, bridging hydroxyls with high H-D exchange reactivity were observed on Zn x Ti y O z (1 0 1) compared with Zn x Ti y O z (0 0 1). The bridging hydroxyls showing rapid proton transfer efficiently stabilizes a transition state of diacetone alcohol intramolecular rearrangement for isobutene production as opposed to the diacetone alcohol dehydration.

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗

DOE OSTI2021

Suppression of antiferromagnetic order and strong ferromagnetic spin fluctuations in Ca(Co 1-x Ni x ) 2-y As 2 single crystals

CaCo 2–y As 2 is a unique itinerant system having strong magnetic frustration. Here, we report the effect of electron doping on the physical properties resulting from Ni substitutions for Co. The single crystals of Ca(Co 1–x Ni x ) 2–y As 2 were characterized by single-crystal x-ray diffraction, energy-dispersive x-ray spectroscopy, magnetization M versus temperature T, magnetic field H, time t, and heat capacity C p (H, T) measurements. The A-type antiferromagnetic (AFM) transition temperature T N = 52 K for x = 0 decreases to 22 K with only 3% Ni substitution and is completely suppressed for x > 0.16. For 0.11 ≤ x ≤ 0.52 strong ferromagnetic (FM) fluctuations develop as revealed by magnetic susceptibility χ(T) = M(T) / H measurements. For x = 0.11 and 0.16 competing AFM and FM interactions result in a reentrant spin-glass behavior below T N , as evidenced by the observations of thermomagnetic hysteresis and magnetic relaxation. Enhanced FM fluctuations are also found for the x = 0.21 and 0.31 crystals, where χ c increases significantly at low T. A large χ anisotropy in these compositions where χ c is up to a factor of two larger than χ ab suggests that the FM spin fluctuations are quasi-1D in nature. Weak ferromagnetic contributions to the magnetization are found at T = 2 K for x = 0.11 –0.31. Heat-capacity Cp(T) measurements reveal the presence of FM quantum spin fluctuations for 0.11 ≤ x ≤ 0.52, where a logarithmic T dependence of Cp(T) / T is observed at low T. Here, the suppression of AFM order by the development of strong FM fluctuations in Ca(Co 1–x Ni x ) 2–y As 2 crystals suggests the presence of a FM quantum-critical point at x ≈ 0.20. Our density-functional theory (DFT) calculations confirm that FM fluctuations are enhanced by Ni substitutions for Co in CaCo 2–y As 2 . The Sommerfeld electronic heat-capacity coefficient is enhanced for x = 0, 0.21, and 0.42 by about a factor of two compared to DFT calculations of the density of states (DOS) at the Fermi energy, suggesting an enhancement of the DOS from electron-phonon and/or electron-electron interactions. The crystals with x > 0.52 do not exhibit FM spin fluctuations or magnetic order at T ≥ 1.8 K, which was found from the DFT calculations to arise from a Stoner transition. Superconductivity is not observed above 1.8 K for any of the compositions. Neutron-diffraction studies of crystals with x = 0.11 and 0.16 in the crossover regime (0.1 ≲ x ≲ 0.2) show no evidence of A-type ordering as observed in the parent compound with x = 0. Furthermore, no other common magnetic structures, such as ferromagnetic (FM), helical stacking of in-plane FM layers, or in-plane AFM structure, are found with an ordered moment greater than the uncertainty of 0.05 μ B per transition-metal atom.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

DOE OSTI2026

SPT-3G D1: Compton-$y$ maps using data from the SPT-3G and Planck surveys

We present thermal Sunyaev-Zel'dovich (tSZ) Compton-$y$ parameter maps constructed from two years (2019-2020) of observations with the South Pole Telescope (SPT) third-generation camera, SPT-3G, combined with data from the Planck satellite. Using a linear combination (LC) pipeline, we obtain a suite of reconstructions that explore different trade-offs between statistical sensitivity and suppression of astrophysical contaminants, including minimum-variance, CMB-deprojected, and CIB-deprojected $y$-maps. We validate these maps through different statistical techniques such as auto- and cross-power spectra with large-scale structure tracers as well as stacking on cluster locations. These tests are used to understand the balance between noise and astrophysical foreground residuals (such as the CIB) in combination with the recovery of the tSZ signal for different maps. For example, results from stacking at the location of clusters confirm the robustness of the recovered tSZ signal over the $\sim 1500\: {\rm deg}^2$ SPT-3G survey field used in this analysis. The high-resolution and low-noise maps produced here provide an important cosmological tool for future studies, including measurements of the Compton-$y$ map power spectrum, cross-correlations with other tracers of the large-scale structure, detailed modeling of cluster pressure profiles, and study of the thermodynamic state of the baryons in the Universe.

Maniyar, A. S. [Harvard-Smithsonian Ctr. Astrophys↗

DOE OSTI2024

Tailoring Ion Transport in Li 3‐3y Ho 1+y Cl 6‐x Br x via Transition‐Metal Free Structural Planes and Charge Carrier Distribution

Abstract Localized atomistic disorder in halide‐based solid electrolytes (SEs) can be leveraged to boost Li + mobility. In this study, Li + transport in structurally modified Li 3 HoCl 6 , via Br − introduction and Li + deficiency, is explored. The optimized Li 3‐3 y Ho 1+ y Cl 6‐ x Br x achieves an ionic conductivity of 3.8 mS cm −1 at 25 °C, the highest reported for holmium halide materials. 6,7 Li nuclear magnetic resonance and relaxometry investigations unveil enhanced ion dynamics with bromination, attaining a Li + motional rate neighboring 116 MHz. X‐ray diffraction analyses reveal mixed‐anion‐induced phase transitions with disproportionate octahedral expansions and distortions, creating Ho‐free planes with favorable energetics for Li + migration. Bond valence site energy analysis highlights preferred Li + transport pathways, particularly in structural planes devoid of Ho 3+ blocking effects. Molecular dynamics simulations corroborate enhanced Li + diffusion with Br − introduction into Li 3 HoCl 6 . Li‐Ho electrostatic repulsions in the (001) plane presumably drive Li + diffusion into the Ho‐free (002) layer, enabling rapid intraplanar Li + motion and exchange between the 2d and 4h sites. Li 3‐3 y Ho 1+ y Cl 6‐ x Br x also demonstrates good battery cycling stability. These findings offer valuable insights into the intricate correlations between structure and ion transport and will help guide the design of high‐performance fast ion conductors for all‐solid‐state batteries.

Chemistry↗

DOE OSTI2020

Local order of orthorhombic weberite-type Y 3 TaO 7 as determined by neutron total scattering and density functional theory calculations

Weberite-type oxides are a family of oxides with A 3 BO 7 stoichiometry that can adopt different space groups depending on chemical composition. There is a discrepancy in previous studies as to whether Y 3 TaO 7 is the orthorhombic C222 1 or the Ccmm space group. Here, we describe the short- and long-range structural properties of weberite-type Y 3 TaO 7 using neutron total scattering data, which has a high sensitivity to the oxygen sublattice. Simultaneous analysis of both short- and long-range structural data via conventional Rietveld and small box modelling demonstrates that Y 3 TaO 7 is best modeled as C222 1 . While the Ccmm describes equally well the long-range structure, pair distribution function analysis revealed that the local atomic configuration can be best modelled as C222 1 . This is corroborated by first-principles calculations that confirm the energetic preference of the C222 1 over Ccmm. Further, neutron total scattering data are reported for the first time for the Y 3 TaO 7 weberite-type ceramics.

36 MATERIALS SCIENCE↗

DOE OSTI2021

Disorder-induced time effect in the antiferromagnetic domain state of Fe 1+ y Te

Herein we report on temperature-dependent soft X-ray absorption spectroscopy (XAS) measurements utilizing linearly polarized synchrotron radiation to probe magnetic phase transitions in iron-rich Fe 1+y Te (y ≈ 0.12). X-ray magnetic linear dichroism (XMLD) signals, which sense magnetic ordering processes at surfaces, start to increase monotonically below the Néel temperature T N = 57 K. This increase is due to a progressive bicollinear antiferromagnetic (AFM) alignment of Fe spins of the monoclinic Fe 1+y Te parent phase. This AFM alignment was achieved by a [1 0 0]-oriented biasing field favoring a single-domain state during cooling across T N . Our specific heat and magnetization measurements confirm the bulk character of this AFM phase transition. On longer time scales, however, we observe that the field-biased AFM state is highly unstable even at the lowest temperature of T = 3 K. After switching off the biasing field, the XMLD signal decays exponentially with a time constant τ = 1506 s. The initial XMLD signal is restored only upon repeating a cycle consisting of heating and field-cooling through T N . We explain the time effect by a gradual formation of a multi-domain state with 90° rotated AFM domains, promoted by structural disorder, facilitating the motion of twin-domains. Significant disorder in our Fe 1+y Te sample is evident from our X-ray diffraction and specific heat data. The stability of magnetic phases in Fe-chalcogenides is an important material property, since the Fe(Te 1-x Se x ) phase diagram shows magnetism intimately connected with superconductivity.

36 MATERIALS SCIENCE↗

DOE OSTI2022

Growth and structural transitions of core-shell nanorods in nanocrystalline Al-Ni-Y

Unique nanorod precipitates with a core-shell structure are found to nucleate from the grain boundaries of a bulk nanocrystalline Al-Ni-Y alloy fabricated via powder consolidation, contributing significantly to stabilization and strengthening. The local structure, chemistry, and evolution of these features during annealing are reported here. In the as-consolidated state, the nanorods can be either structurally ordered or disordered, yet a consistent chemical patterning is found where the core is primarily Al plus C while the shell is enriched with Y. As annealing time increases, more nanorods transform to an ordered structure as they coarsen while the core composition remains unchanged. In contrast, the shell chemistry transitions from Y-rich to Ni-rich with longer annealing treatments, most likely due to the different diffusivities of Y and Ni in Al. Furthermore, a spatial and chemical correlation between the nanorods and amorphous complexions is observed, suggesting that these complexions serve as preferential nucleation sites.

36 MATERIALS SCIENCE↗

DOE OSTI2023

Ethylene Hydrogenation Molecular Mechanism on MoC y Nanoparticles

Ethylene hydrogenation catalyzed by MoC y nanoparticles has been studied by means of density functional theory methods and several models. These include MetCar (Mo 8 C 12 ), Nanocube (Mo 14 C 13 ), and Mo 12 C 12 nanoparticles as representatives of experimental MoC y nanostructures. The effect of hydrogen coverage has been studied in detail by considering low-, intermediate-, and high-hydrogen regimes. The calculated enthalpy and energy barriers show that ethylene hydrogenation is feasible on the MetCar, Mo 12 C 12 , and Nanocube but at low, medium, and high hydrogen coverages, respectively. An additional step, related to the H* migration from a Mo to a C site in the nanoparticle, has been found to be the key to establishing the best hydrogenation system. In most cases, the reactions are exothermic, featuring low hydrogenation energy barriers, especially for the Nanocube at high hydrogen coverage. In addition, the calculated adsorption Gibbs free energy shows that, for this system, the C 2 H 4 adsorption is feasible in the 300–400 K temperature range and pressures from 10 –10 to 2 atm. For the hydrogenation steps, calculated transition state theory rates show that the overall process is limited by the first hydrogenation step (C 2 H 4 → C 2 H 5 ) at temperatures of 330–400 K. However, at the lower temperatures of 300–320 K, the reaction rates are comparable for the two steps. The present results indicate that the Mo 14 C 13 Nanocube models of MoC y nanoparticles exhibit appropriate thermodynamic and kinetic features to catalyze ethylene hydrogenation at a high-hydrogen-coverage regime. The present findings provide a basis for understanding the chemistry of active MoC y catalysts, suggest appropriate working conditions for the reaction to proceed, and provide a basis for future experimental studies.

03 NATURAL GAS↗

DOE OSTI2024

Reverse Polarizability of Rare Earth Ions (La 3+ , Gd 3+ , Lu 3+ , Y 3+ ) in Tellurite Glasses and Glass Ceramics for Optical Limiting

All-optical modulation using inherent third-order optical nonlinearity of a medium has garnered considerable interest in photonics and optoelectronics. Herein, nonlinear optical (NLO) properties of tellurite glasses and glass ceramics (GCs) containing four different rare earths (RE = La, Gd, Lu, and Y) have been deliberated in near-infrared regions under an ultrafast regime. The La-based glass exhibits ~10 times higher nonlinear refraction (n 2 ) and absorption (α 2 ) than reported NLO materials. The NLO susceptibility [χ (3) ] trend in the studied glasses is La > Gd > Lu > Y, matching with RE 3+ polarizability. Furthermore, Ln 2 Te 6 O 15 nanocrystallite-embedded transparent GCs exhibit a larger NLO coefficient due to the enhanced local field from oxygen vacancies in crystallites. Interestingly, the trend of χ (3) in GCs follows the sequence of Y > Lu > Gd > La, precisely opposite to the glasses. This observation challenges the general polarizability approach of RE 3+ ions, emphasizing that quadratic hyperpolarizability of RE 3+ is pivotal for NLO properties of GCs. Among the studied matrices, Y-containing GCs showed the lowest optical limiting (OL) threshold (5.4 mJ/cm 2 at 800 nm), much lower than those of the reported NLO materials, suggesting its potential as a femtosecond NIR-laser safety material. A combination of large α 2 and n 2 from the studied matrices indicates their advantage for harmonic generation, potentially aiding in the design of ultrafast signal processing devices.

36 MATERIALS SCIENCE↗

DOE OSTI2020

The role of mixed vibronic Q y -Q x states in green light absorption of light-harvesting complex II

The importance of green light for driving natural photosynthesis has long been underappreciated, however, under the presence of strong illumination, green light actually drives photosynthesis more efficiently than red light. This green light is absorbed by mixed vibronic Q y -Q x states, arising from chlorophyll (Chl)-Chl interactions, although almost nothing is known about these states. Here, we employ polarization-dependent two-dimensional electronic-vibrational spectroscopy to study the origin and dynamics of the mixed vibronic Q y -Q x states of light-harvesting complex II. We show the states in this region dominantly arise from Chl b and demonstrate how it is possible to distinguish between the degree of vibronic Q y versus Q x character. We find that the dynamics for states of predominately Chl b Q y versus Chl b Q x character are markedly different, as excitation persists for significantly longer in the Q x states and there is an oscillatory component to the Q x dynamics, which will be discussed. Our findings demonstrate the central role of electronic-nuclear mixing in efficient light-harvesting and the different functionalities of Chl a and Chl b .

59 BASIC BIOLOGICAL SCIENCES↗

DOE OSTI2022

Fe 1+ y Te x Se1- x : A Delicate and Tunable Majorana Material

Here, we report the observation for the p z electron band and the band inversion in Fe 1 + y Te x Se 1–x with angle-resolved photoemission spectroscopy. Furthermore, we found that excess Fe (y > 0) inhibits the topological band inversion in Fe 1 + y Te x Se 1 – x , which explains the absence of Majorana zero modes in previous reports for Fe 1+y Te x Se 1 – x with excess Fe. Based on our analysis of different amounts of Te doping and excess Fe, we propose a delicate topological phase in this material. Thanks to this delicate phase, one may be able to tune the topological transition via applying lattice strain or carrier doping.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

DOE OSTI2023

Diagnosis of 3D magnetic field and mode composition in MHD turbulence with Y -parameter

ABSTRACT Magnetic fields are crucial in numerous astrophysical processes within the interstellar medium (ISM). However, the detailed determination of magnetic field geometry is notoriously challenging. Based on the modern magnetohydrodynamic (MHD) turbulence theory, we introduce a novel statistical technique, the ‘Y-parameter’, to decipher the magnetic field inclination in the ISM and identify dominant turbulence modes. The Y-parameter, calculated as the ratio of anisotropies of different Stokes parameter combinations, displays contrasting trends with the mean-field inclination angle in Alfvénic and compressible turbulence modes. A Y-parameter value around 1.5 ± 0.5 provide a statistical boundary to determine the dominant MHD turbulence modes. We have discovered specific correlations between the Y-parameter value and the inclination angle that unveil the dominant turbulence mode. This methodology, when applied to future radio polarization surveys such as LOFAR and SKA, promises to significantly enhance our knowledge of 3D magnetic field in the ISM and improve our understanding of interstellar turbulence.

79 ASTRONOMY AND ASTROPHYSICS↗

DOE OSTI2020

Enhancing superconductivity of Y 5 Rh 6 Sn 18 by atomic disorder

Here, we investigate the effect of enhancement of superconducting transition temperature $T_c$ by nonmagnetic atom disorder in the filled skutterudite-related tetragonal Y 5 Rh 6 Sn 18 compound doped with Ca. We documented experimentally that Y 5 Rh 6 Sn 18 and its Ca-doped alloys are electronically inhomogeneous at the nanoscale, when Ca content is smaller than ~1.5 in the Y 5– x Ca x Rh 6 Sn 18 system, while for $\textit{x}$ ≥ 1.5 much stronger chemical phase inhomogeneity is observed with an about 20% volume fraction of the second 3:4:13 cubic phase, which we interpret as a fluctuation of stoichiometry within the bulk sample. Then the enhancement of $T_c$ vs $\textit{x}$ could be modeled by a mechanism proposed in recent theoretical reports for increasing the mean-field transition temperature $T_c$ in the presence of nonmagnetic disorder. The increase in disorder with doping increases the sample inhomogeneity and causes a systematic increase in $T_c$, while for two-phase $\textit{x}$ ≥ 1.5 samples the critical temperature $T^{\star}_c ≈ 2 × T_c$ rapidly increases. Based on band structure calculations performed under pressure, we demonstrate how the change in density of states would affect $T_c$ of Y 5 Rh 6 Sn 18 . We obtained the Grüneisen parameter $γ_G$ larger for the inhomogeneous phase with respect to $γ_G$ of the bulk $T_c$ phase and attribute the enhancement of $T_c$ to larger stiffening of the high-temperature $T^{\star}_c$ phase.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

DOE OSTI2021

Robust antiferromagnetism in Y 2 Co 3

We report on a solution-growth based method to synthesise single crystals of Y 2 Co 3 and on its structural and magnetic properties. We find that Y 2 Co 3 crystallizes in the La 2 Ni 3 -type orthorhombic structure with space group Cmce (No. 64), with Co forming distorted kagome lattices. Y 2 Co 3 orders antiferromagnetically below TN=252 K. Magnetization measurements reveal that the moments are primarily aligned along the b axis with evidence for some canting. Band-structure calculations indicate that ferromagnetic and antiferromagnetic orders are nearly degenerate, at odds with experimental results. Magnetization measurements under pressure up to 1 GPa reveal that the Néel temperature decreases with the slope of -1.69 K/GPa. We observe a field-induced spin-flop transition in the magnetization measurements at 1.5 K and 21 T with magnetic field along the b direction. The magnetization is not saturated up to 35 T, indicating that the antiferromagnetic ordering in Y 2 Co 3 is quite robust, which is surprising for such a Co-rich intermetallic.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

DOE OSTI2024

Superstructures and magnetic order in heavily Cu-substituted ( Fe 1 – x Cu x ) 1 + y Te

Most iron-based superconductors exhibit stripe-type magnetism, characterized by the ordering vector Q = ($\frac{1}{2},\frac{1}{2}$). In contrast, Fe 1+y Te, the parent compound of the Fe 1+y Te 1–x Se x superconductors, exhibits double-stripe magnetic order associated with the ordering vector Q = ($\frac{1}{2},0$). Here, we use elastic neutron scattering to investigate heavily Cu-substituted (Fe 1–x Cu x ) 1+y Te compounds and reveal that (1) for x ≳ 0.4, short-range magnetic order emerges around the stripe-type vector at Q = ($\frac{1}{2}$ ± δ, $\frac{1}{2}$ ± δ, $\frac{1}{2}$) with δ ≈ 0.05; (2) the short-range magnetic order is associated with a superstructure modulation at Q = ($\frac{1}{3},\frac{1}{3},\frac{1}{2}$), with the magnetic correlation length shorter than that for the superstructure; and (3) for x ≳ 0.55, we observe an additional intergrown phase with higher Cu content, characterized by a superstructure modulation vector Q = ($\frac{1}{3},\frac{1}{3},0$) and magnetic peaks at Q = ($\frac{2}{3},\frac{1}{3},\frac{1}{2}$)/($\frac{1}{3},\frac{2}{3},\frac{1}{2}$). The positions of superstructure peaks suggest that relative to the tetragonal unit cell of Fe 1+y Te, heavy Cu substitution leads to Fe-Cu orderings that expand the unit cell by $\sqrt{2}$ × 3$\sqrt{2}$ times in the ab plane, corroborated by first-principles calculations that suggest the formation of spin chains and spin ladders. Finally, our findings show that stripe-type magnetism is common in magnetically diluted iron pnictides and chalcogenides, despite the varying associated atomic orderings

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗

DOE OSTI2025

Deuteron-induced reactions on natural Zr from threshold to 50 MeV: production of 86g Y

Two stacks of thin Zr foils were irradiated with 30 and 50 MeV deuterons, respectively, using the Lawrence Berkeley National Laboratory 88-Inch Cyclotron, and 19 excitation functions for nat Zr(d,x) reactions were measured over a beam energy range of 6.3–47.64 MeV, where the independent cross sections for nat Zr(d,x) 88 Nb and nat Zr(d,x) 86m,g Y were measured for the first time. The well-characterized nat Fe(d,x) 56 Co, nat Ni(d,x) 56 Co, nat Ni(d,x) 58 Co, nat Ni(d,x) 61 Cu, nat Ti(d,x) 46 Sc and nat Ti(d,x) 48 V monitor reactions were used to determine the deuteron beam current throughout the stacks. All cross sections were determined using High Purity Germanium (HPGe) detector γ-ray spectroscopy. A variance minimization technique was employed to simultaneously constrain the deuteron beam currents with multiple monitor reactions, thus reducing systematic uncertainties. An additional 16 channels are reported for reactions on the nickel, titanium, and iron monitor foils, leading to a total of 35 excitation functions, with seven reaction channels reported for the first time in this work. The measured excitation functions are compared to calculations provided by the reaction modeling codes TALYS – 2.0, ALICE – 2020, CoH – 3.5.3 and EMPIRE – 3.2.3, as well as the TENDL – 2023 data library. The degree of agreement between theory and experiments is discussed. The possible production of the important PET radionuclide 86g Y via the nat Zr(d,x) route was critically examined. The physical yields for nat Zr(d,x) 86 Y and other yttrium isotopes produced were calculated and compared to other production pathways. Due to high-level of associated radionuclide impurities, this route cannot deliver 86g Y suitable for medical applications.

86gY↗