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

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At least 109 records · Page 6
All sourcesNASA NTRSDOE OSTI
DOE OSTI2022

BiCuI 4 (Pyridine) 5 a neutral ligand-supported compound of BiI 3 and CuI

Reaction of equimolar pyridine (Py) solutions BiI 3 and CuI produces the Py-supported 1:1 bimetallic complex BiCuI 4 (Py) 5 in quantitative yield. The title complex is only the second neutral complex to feature Cu–I–Bi bridging and shows an octahedral trans-[BiI 4 (Py) 2 ] unit joined to a distorted tetrahedral CuI(Py) 3 unit by an iodide bridge. The complex shows low thermal stability, decomposing under modest heating or vacuum to produce a mixture of BiI 3 and CuI. Thus, it is a potential entry/precursor to BiI 3 /CuI chemistry. Natural Localized Molecular Orbital (NLMO) calculations were performed to analyze the nature of the Cu–I–Bi bonds, revealing that the title compound lies on the cusp of being [Cu(Py) 3 ] + [BiI 4 (Py) 2 ] – . Diffuse reflectance spectroscopy measurements show a strong absorption band with an optical bandgap energy of 1.94 eV. Theoretical density of states (DOS) and time-dependent density functional theory (TD-DFT) experiments to map the electronic structure assign the primary electronic transition as a mixed halide/metal-to-ligand charge transfer between Cu–I–Bi donor orbitals and Py π* acceptor orbitals.

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

Spin-orbital correlations from complex orbital order in MgV 2⁢ O 4

MgV 2 ⁢O 4 is a spinel based on magnetic V 3+ ions, which host both spin (𝑆 = 1) and orbital (𝑙 eff = 1) moments. Owing to the underlying pyrochlore coordination of the magnetic sites, the spins in MgV 2 ⁢O 4 only antiferromagnetically order once the frustrating interactions imposed by the 𝐹⁡𝑑⁢$\overline{3}$⁢𝑚 lattice are broken through an orbitally-driven structural distortion at T 𝑆 ≃ ⁢60 K. Consequently, a Néel transition occurs at T 𝑁 ≃ ⁢40 K. Low-temperature spatial ordering of the electronic orbitals is fundamental to both the structural and magnetic properties; however, considerable discussion on whether it can be described by complex or real orbital ordering is ambiguous. We apply neutron spectroscopy to resolve the nature of the orbital ground state and characterize hysteretic spin-orbital correlations using x-ray and neutron diffraction. Neutron spectroscopy finds multiple excitation bands and we parametrize these in terms of a multilevel (or excitonic) theory based on the orbitally degenerate ground state. Meaningful for the orbital ground state, we report an “optical-like” mode at high energies that we attribute to a crystal-field-like excitation from the spin-orbital 𝑗 eff = 2 ground-state manifold to an excited 𝑗 eff =1 energy level. We parametrize the magnetic excitations in terms of a Hamiltonian with spin-orbit coupling and local crystalline electric field distortions resulting from deviations from perfect octahedra surrounding the V 3+ ions. We suggest that this provides compelling evidence for complex orbital order in MgV 2⁢ O 4 . We then apply the consequences of this model to understand hysteretic effects in the magnetic diffuse scattering where we propose that MgV 2⁢ O 4 displays a high-temperature orbital memory of the low-temperature spin order.

Frustrated magnetism↗
DOE OSTI2020

Probing the Electronic Structure of a Thorium Nitride Complex by Solid-State 15N NMR Spectroscopy

The solid-state 15N NMR powder spectra of the thorium nitride complex, [K(18-crown-6)(THF)2][(R2N)3Th(m-15N)(Th(NR2)3] ([K][1-15N], R = SiMe3), and the thorium amide complex, [Th(NR2)3(15NH2)] (2-15N) were recorded. The spectrum for [K][1-15N] represents the first reported solid-state 15N NMR data for an actinide nitride complex. The experimentally measured tensor spans are 847 ppm for [K][1-15N] and 237 ppm for 2-15N. Both shielding tensors exhibit a near-zero asymmetry parameter, which for [K][1-15N] is consistent with a local rotational symmetry of its 15N-labelled nitride ligand. For 2-15N, the lack of asymmetry can be rationalized by a quasi-free Th-NH2 bond rotation in the solid-state. DFT calculations overestimate the tensor span somewhat for [K][1-15N], but provide isotropic shifts in good agreement with both the solid-state and solution values for both complexes. Natural localized molecular orbital (NLMO) analyses of the nuclear shielding reveal that the larger tensor span in [K][1-15N] vs. 2-15N is primarily a consequence of more pronounced covalency of the N-Th bonds, and large spin-orbit coupling due to significant Th 5f orbital contribution to those bonds, impacting the principal components of the shielding tensor perpendicular to the Th-N-Th axis. Overall, our analysis confirms the involvement of the 5f orbitals in Th-N multiple bonds, and further demonstrates the value of solid-state NMR spectroscopy for interrogating actinide-ligand bonding.

actinides, covalent bonding, Nuclear Magnetic Reso↗
DOE OSTI2022

Long-term Evolution of Tightly Packed Stellar Black Holes in AGN Disks: Formation of Merging Black Hole Binaries via Close Encounters

We study the long-term evolution of two or more stellar black holes (BHs) on initially separated but unstable circular orbits around a supermassive BH (SMBH). Such a close-packed orbital configuration can naturally arise from BH migrations in the AGN disk. Dynamical instability of the orbits leads to recurring close encounters between two BHs, during which the BH separation r p becomes less than the Hill radius R H . In rare very close encounters, a tight merging BH binary can form with the help of gravitational wave emission. We use N-body simulations to study the time evolution of close encounters of various degrees of closeness. For a typical "SMBH+2BH" system, the averaged cumulative number of close encounters (with r p ≲ R H ) scales approximately as ∝ t 0.5 . The minimum encounter separation r p follows a cumulative distribution P( p ) ∝ r p for r p « R H . We obtain a semi-analytical expression for the averaged rate of binary captures that lead to BH mergers. Our results suggest that close-packed BHs in AGN disks may take a long time (≳10 7 orbits around the SMBH) to experience a sufficiently close encounter and form a bound binary. This time can be shorter if the initial BH orbits are highly aligned. The BH binary mergers produced in this scenario have high eccentricities when entering the LIGO band and broad distribution of orbital inclinations relative to the original AGN disk. We explore the effects of the gas disk and find that simple gas drags on the BHs do not necessarily lead to an enhanced BH binary capture rate.

79 ASTRONOMY AND ASTROPHYSICS↗
DOE OSTI2023

Novel Phases and Dynamics of Multi-orbital Mott Insulators

The goal of this project is to gain theoretical insight into magnetism in the presence of spin-orbit coupling (SOC) for multi-orbital Mott insulators. Inspired by the exact solution of the Kitaev model that harbors a quantum spin liquid with novel excitations and struck by its relevance for materials with anisotropic orbital interactions, the PI will explore various new classes of 4d and 5d transition metal oxides. Starting with all electron Hamiltonians, the PI will derive minimal magnetic models. The aim will be to understand the role played by orbital frustration, even in the absence of any geometric frustration, in creating orbitally ordered as well as spin-orbital liquid phases. Orbital frustration arises primarily from the directional or anisotropic nature of d-orbitals in contrast to the isotropic nature of the spin degree of freedom. These models will be investigated by a variety of theoretical and numerical methods, including exact diagonalization, mean field theories, density matrix renormalization group and quantum Monte Carlo methods. Testable predictions for three experiments: nuclear magnetic resonance (NMR) and resonant x-ray scattering (RXS) to probe orbital ordering and pump-probe experiments to probe quantum dynamics will test the validity of these models for materials.

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2024

Spin Berry curvature-enhanced orbital Zeeman effect in a kagome metal

Berry phases and the related concept of Berry curvature can give rise to many unconventional phenomena in solids. Here, we discover a colossal orbital Zeeman effect of topological origin in a bilayer kagome metal, TbV 6 Sn 6 . Using spectroscopic imaging scanning tunnelling microscopy, we reveal that the magnetic field leads to a splitting of the gapped Dirac dispersion into two branches with enhanced momentum-dependent g factors, resulting in a substantial renormalization of the Dirac band. These measurements provide a direct observation of a magnetic field-controlled orbital Zeeman coupling to the orbital magnetic moments of up to 200 Bohr magnetons near the gapped Dirac points. Our work provides direct insight into the momentum-dependent nature of topological orbital moments and their tunability via the magnetic field, concomitant with the evolution of the spin Berry curvature. Furthermore, these results can be extended to explore large orbital magnetic moments driven by the Berry curvature governed by other quantum numbers beyond spin, such as the valley in certain graphene-based structures.

36 MATERIALS SCIENCE↗
DOE OSTI2025

First fluctuation measurements using an Imaging Neutral Particle Analyzer on DIII-D

A recent upgrade to the Imaging Neutral Particle Analyzer (INPA) on DIII-D has allowed for the first fluctuation measurements using an INPA to be taken during a neoclassical tearing mode (NTM). The INPA signal tracked the mode over 150 ms as the mode frequency dropped to zero, capturing both the NTM with poloidal and toroidal mode numbers $m/n=2/1$ and a $3/2$ mode at double the frequency. Analysis shows that the signals originate from charge exchange events near the edge of the plasma, and relative fluctuation amplitudes are greater than 25% for the duration of the NTM. Filtered signals show frequency beating patterns that are phase-space dependent. Simulated signal is dominated by prompt transport from the neutral beams to the INPA sightline, while the contribution from the slowing down distribution is significantly lower. Simulated measurements in the range of pitches that the diagnostic is sensitive to (0.5≤|v∥/v|≤ 0.75) show the signal is dominated by trapped orbits that pass through magnetic islands near the edge of the plasma. Calculations of expected fluctuation levels show that only direct interaction with the NTM can provide the strong relative fluctuation levels seen experimentally. The prompt nature of the orbits and thin radial layer found to contribute to synthetic signals suggest INPA passive data may be used to measure the perturbations of confined orbits on a single pass through a plasma instability.

70 PLASMA PHYSICS AND FUSION TECHNOLOGY↗
DOE OSTI2021

Correlation-assisted quantized charge pumping

Here, we investigate charge pumping in the vicinity of order-obstructed topological phases, i.e., symmetry-protected topological phases masked by spontaneous symmetry breaking in the presence of strong correlations. To explore this, we study a prototypical Su-Schrieffer-Heeger model with finite-range interaction that gives rise to orbital charge density wave order and characterize the impact of this order on the model's topological properties. In the ordered phase, where the many-body topological invariant loses quantization, we find that not only is quantized charge pumping still possible, but it is even assisted by the collective nature of the orbital charge density wave order. Remarkably, we show that the Thouless pump scenario may be used to uncover the underlying topology of order-obstructed phases.

1-dimensional systems↗
DOE OSTI2023

Insight into the Structural and Emissive Behavior of a Three‐Dimensional Americium(III) Formate Coordination Polymer

Abstract We report the structural, vibrational, and optical properties of americium formate (Am(CHO 2 ) 3 ) crystals synthesized via the in situ hydrolysis of dimethylformamide (DMF). The coordination polymer features Am 3+ ions linked by formate ligands into a three‐dimensional network that is isomorphous to several lanthanide analogs, (e. g., Eu 3+ , Nd 3+ , Tb 3+ ). Structure determination revealed a nine‐coordinate Am 3+ metal center that features a unique local C 3v symmetry. The metal–ligand bonding interactions were investigated by vibrational spectroscopy, natural localized molecular orbital calculations, and the quantum theory of atoms in molecules. The results paint a predominantly ionic bond picture and suggest the metal‐oxygen bonds increase in strength from Nd−O 5 D 1′ → 7 F 0′ emission band is observed and dominates the emission spectrum. This behavior is unusual and is attributed to the C 3v coordination environment of the metal center.

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

Americium Oxalate: An Experimental and Computational Investigation of Metal–Ligand Bonding

A novel actinide-containing coordination polymer, [Am(C 2 O 4 )(H 2 O) 3 Cl] (Am-1), has been synthesized and structurally characterized. The crystallographic analysis reveals that the structure is two-dimensional and comprised of pseudo-dimeric Am 3+ nodes that are bridged by oxalate ligands to form sheets. Each metal center is nine-coordinate, forming a distorted capped square antiprism geometry with a C 1 symmetry, and features bound oxalate, aqua, and chloro ligands. The Am 3+ –ligand bonds were probed computationally using the quantum theory of atoms in molecules nd natural localized molecular orbital approaches to investigate the underlying mechanisms and hybrid atomic orbital contributions therein. The analyses indicate that the bonds within Am-1 are predominantly ionic and the 5f shell of the Am 3+ metal centers does not add a significant covalent contribution to the bonds. Further, our bonding assessment is supported by measurements on the optical properties of Am-1 using diffuse reflectance and photoluminescence spectroscopies. The position of the principal absorption band at 507 nm ( 5 L 6' ← 7 F 0' ) is notable because it is consistent with previously reported americium oxalate complexes in solution, indicating similarities in the electronic structure and ionic bonding. Compound Am-1 is an active phosphor, featuring strong bright-blue oxalate-based luminescence with no evidence of metal-centered emission.

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

Elucidation of an Unusually Long Pu–N Bond in a Plutonium(III)-Tetrazolate Complex

Four trivalent, f-element tetrazolate hydrate complexes [M(H 2 O) 9 ](Hdtb) 3 ·nH 2 O (Nd1, n = 7 and Pu1, n = 9; dtb 2– = 1,3-di(tetrazolate-5-yl)benzene) and [M(Hdtb)(H 2 O) 8 ](dtb)·11H 2 O (Nd2 and Pu2) were prepared using metathesis reactions. These complexes contain hydrated M(III) cations, but in the latter complexes, Nd2 and Pu2, one of the water molecules has been displaced by a long interaction between the M(III) cation and a Hdtb – anion. Notably, the Pu(III)–N bond in Pu2, representing the longest IX Pu(III)–N ( IX = nine coordinate) bond reported has a length of 2.8338(15) Å and is slightly shorter than the Nd(III)–N bond length of 2.8425(13) Å in Nd2. Analysis of bond lengths, Wiberg bond indices (WBI), natural localized molecular orbitals (NLMOs), and quantum theory of atoms in molecules (QTAIM) reveals that the metal contribution to the Pu(III)–N bond is marginally greater than that of the Pu(III)–OH 2 bonds in Pu2 and the Nd(III)–N bond in Nd2. Thus, this rather long M–N interaction provides an example where the expectation that An(III) compounds exhibit greater covalency with soft donor ligands compared to harder ligands fails. Furthermore, the absorption spectra of Pu1 and Pu2 further support this observation, highlighting a surprising degree of similarity in their electronic structures.

Covalent bonding↗
DOE OSTI2025

Unveiling Unusual Reactivity of SO 2 and Unusual Type of S–X Long Bonds

A new reactivity of SO 2 to form unusual stable M−X−SO 2 (X = F, Cl, H) complexes is unveiled in this study. Moreover, a new type of S−X long bonds, which are significantly longer than traditional S−X covalent bonds, has been discovered. The P,N-ligated Ni−F complex model 1A can bind a SO 2 molecule through the new F−S long bond (2.207 Å), and a stable Ni−F−SO 2 complex 1B is generated, being exergonic by 2.2 kcal/mol. According to natural localized molecular orbital analysis, the new S−F long bond has a unique p(F) → π*(O=S=O) bonding interaction, which is shown to arise from the long S−F length. In comparison, the strength of the new F−S long bond (−2.2 kcal/mol) is found to be significantly stronger than common noncovalent interactions such as the hydrogen and halogen bond. The substituent modulations suggest that the electron-donating groups can increase the strength of new F−S bonds and enhance binding free energies ΔG bind . The scope of possible M−X complexes was explored, and various metals and X (F, Cl, and H) ligands were found to form stable M−X−SO 2 complexes. Specifically, the anionic M−X complexes display much higher ΔG bind values, ranging from −8 to −10 kcal/mol. The study paves the way for a green, recyclable, and adjustable SO 2 absorption method.

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

Trans-Influence in Dinuclear Pt(III) Complexes: Electronic Structure, σ-Donation, and Pt–Pt Spin–Spin Coupling

This study investigates the trans influence in dinuclear platinum(III) complexes using a combined approach of ab initio molecular dynamics and natural localized molecular orbital (NLMO) analysis. Focusing on pivalamidate-bridged Pt III complexes with axial ligands of varying σ-donation strength, it is quantified how ligand−metal interactions propagate through the Pt−Pt bond, and how they affect bond polarization, axial water coordination, and 1 J PtPt spin−spin coupling constants. NLMO analysis reveals quantitatively that strong σ-donating ligands polarize the Pt−Pt bond, shifting the electron density toward the opposite platinum center. The polarization mechanism is identified as the primary reason for the observed reduction of 1 J PtPt , because the bond polarization diminishes the transmission of the nuclear magnetic spin-induced electron spin density through the Pt−Pt bond. Additionally, the destabilization of axial water coordination at the opposite Pt site can be rationalized through a polarizationinduced Pt IV − Pt II -like mixed-valence character.

Ab initio molecular dynamics↗
DOE OSTI2022

Orbital selective Kondo effect in heavy fermion superconductor UTe2

Abstract Heavy fermion systems emerge from the collective Kondo effect, and their superconductivity can serve as a promising platform for realizing next-generation quantum technologies. However, it has been a great challenge to explore many-body effects in heavy fermion systems with ab-initio approaches. We computed the electronic structure of UTe 2 without purposive judgements, such as intentional selection of on-site Coulomb interaction and disregarding spin-orbit coupling. We show that U-5 f electrons are highly localized in the paramagnetic normal state, giving rise to the Kondo effect. It is also found that the hybridization between U-5 f and U-6 d predominantly in the orthorhombic a b -plane is responsible for the high-temperature Kondo effect. In contrast, the hybridization between U-5 f and Te-5 p along the c -axis manifests the Kondo scattering at a much lower temperature, which could be responsible for the low-temperature upturn of the c -axis resistivity. Our results show that the electron correlation in UTe 2 is orbital selective, which naturally elucidates the recent experimental observations of anomalous temperature dependence of resistivity. Furthermore, we suggest that the Kondo effect is suppressed at high pressure owing to weak localization of magnetic moments, which results from enhanced U-5 f electron hopping. Our discovery provides significant insight toward understanding anisotropic quantum behavior including selective re-entrant superconductivity in heavy fermion UTe 2 .

75 CONDENSED MATTER PHYSICS, SUPERCONDUCTIVITY AND↗
DOE OSTI2024

Hopping frustration-induced flat band and strange metallicity in a kagome metal

The introduction of localized electronic states into a metal can alter its physical properties, for example enabling exotic metal physics including heavy fermion and strange metal behaviour. A common source of localized states in such systems are partially filled 4f and 5f shells because of the inherently compact nature of those orbitals. The interaction of electrons in these orbitals with the conduction sea is well described by the Kondo framework. However, there have also been observations of Kondo-like behaviour in 3d transition metal oxides and in 4d- and 5d-containing van der Waals heterostructures. This calls for a broader consideration of the physical requirements for Kondo systems. Here we show transport and thermodynamic hallmarks of heavy fermion and strange metal behaviour that arise in the kagome metal Ni3In, wherein the source of localized states is destructive interference-induced band flattening of partially filled Ni 3d states. With magnetic field and pressure tuning, here we also find evidence that the system is proximate to quantum criticality, extending the analogy to f-electron Kondo lattices. These observations highlight the role of hopping frustration in metallic systems as a potential source for strong correlations. Additionally, this suggests a lattice-driven approach to realizing correlated metals with non-trivial band topology.

36 MATERIALS SCIENCE↗
DOE OSTI2025

Unveiling the covalency of versatile Pu(iii)-N bonds in a unique plutonium(iii) complex

A trivalent plutonium–pyrazinyl–tetrazolate complex Na 2 [Pu(Hdtp)(dtp) 2 (H 2 O) 4 ]·9H 2 O (Pu_dtp, H 2 dtp = 2,3-di-1H-tetrazol-5-ylpyrazine) was synthesized through metathesis reaction of plutonium bromide and Na 2 (dtp)·2H 2 O in water. This structure is particularly notable among complexes formed by trivalent f-elements and the dtp 2− ligand in aqueous media. In contrast to other trivalent f-elements, including all Ln 3+ (with the exception of Pm 3+ ) and Cm 3+ , preferentially coordinated with eight water molecules rather than the nitrogen donors of the dtp 2− ligand, Pu 3+ exhibits a distinct affinity for nitrogen coordination. This observation provides strong evidence that the 5f electrons in Pu 3+ are more delocalized than other studied trivalent f-elements. In Pu_dtp, three distinct Pu(III)–N bonds are present: one Pu(III)–N5 from pyrazinyl, one Pu(III)–N4 from the least electronegative nitrogen in the tetrazolate, and three Pu(III)–N1/N2/N3 from the most electronegative nitrogens in the tetrazolate. Experimental Pu(III)–N bond lengths, Wiberg bond indices (WBI), natural localized molecular orbitals (NLMO), quantum theory of atoms in molecules (QTAIM), and energy decomposition analysis (EDA), reveal a covalency trend: Pu(III)–N from the most electronegative nitrogen in tetrazolate > Pu(III)–N from the least electronegative nitrogen in tetrazolate > Pu(III)–N from pyrazinyl. This trend arises from the increased negative charge on the most electronegative nitrogen atoms in the tetrazolate ring, enhancing electrostatic Pu–N1/N2/N3 interactions. These stronger electrostatic interactions lead to shorter bond lengths, thereby enhancing orbital overlap and greater covalency, compared to the less electronegative nitrogen in tetrazolate (Pu–N4) and the neutral pyrazinyl nitrogen (Pu–N5).

Bai, Zhuanling [Colorado School of Mines, Golden, ↗
DOE OSTI2021

The surroundings of the Milky Way globular cluster NGC 6809

ABSTRACT We study the outer regions of the Milky Way globular cluster NGC 6809 based on Dark Energy Camera observations, which reach nearly 6 mag below the cluster main-sequence (MS) turn-off. In order to unveil its fainter outermost structure, we built stellar density maps using cluster MS stars, once the contamination of field stars was removed from the cluster colour–magnitude diagram. We found that only the resulting stellar density map for the lightest stars exhibits some excesses of stars at opposite sides from the cluster centre that diminish soon thereafter at ∼ 0.32°.Studied globular clusters with apogalactic distances smaller than that of NGC 6809 (5.5 kpc) do not have observed tidal tails. The lack of detection of tidal tails in the studied inner globular cluster sample could be due to the reduced diffusion time of tidal tails by the kinematically chaotic nature of the orbits of these globular clusters, thus shortening the time interval during which the tidal tails can be detected. Further investigations with an enlarged cluster sample are needed to confirm whether chaotic and non-chaotic orbits are responsible for the existence of globular clusters with tidal tails and those with extra-tidal features that are different from tidal tails or without any signatures of extended stellar density profiles.

Piatti, Andrés E.↗
DOE OSTI2021

Natural Charge-Transfer Analysis: Eliminating Spurious Charge-Transfer States in Time-Dependent Density Functional Theory via Diabatization, with Application to Projection-Based Embedding

For many types of vertical excitation energies, linear-response time-dependent density functional theory (LR-TDDFT) offers a useful degree of accuracy combined with unrivaled computational efficiency, although charge-transfer excitation energies are often systematically and dramatically underestimated, especially for large systems and those that contain explicit solvent. As a result, low energy electronic spectra of solution-phase chromophores often contain tens to hundreds of spurious charge-transfer states, making LR-TDDFT needlessly expensive in bulk solution. More nefariously, intensity borrowing by the low-energy charge-transfer states can affect intensities of the valence excitations even if those excitation energies are accurate. At higher excitation energies, it is difficult to distinguish spurious CT states from genuine charge-transfer-to-solvent (CTTS) excitations. In this work, we introduce an automated diabatization scheme that enables fast and effective screening of the CTTS acceptor space in bulk solution. Our procedure introduces the concept of “natural charge-transfer orbitals”, which provide a means to isolate characteristic pairs of orbitals that are most likely to participate in a CTTS excitation. The projection of these orbitals onto solvent-centered virtual orbitals provides a criterion for defining the most important solvent molecules in a given excitation. We apply this method to analyze an ab initio molecular dynamics (MD) trajectory of I-(aq) and report the lowest-energy CTTS band in the absorption spectrum. Our results are in excellent agreement with experimental measurements for bulk I-(aq), and only one-third of the water molecules in the I-(H2O)96 simulation cell need to be described with LR-TDDFT in order to obtain excitation energies that are converged to < 0.1 eV. The tools introduced herein will improve the accuracy, efficiency, and usability of LR-TDDFT in solution-phase environments

Carter-Fenk, Kevin D.↗