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All sourcesNASA NTRSDOE OSTI
DOE OSTI2025

Completion of Transport Property Measurements on Multiple Actinide Fluoride Mixtures

One of the missions of the US Department of Energy’s Office of Nuclear Energy (DOE-NE) Molten Salt Reactor (MSR) Campaign under the Advanced Reactor Technology program has been to experimentally measure thermophysical properties of MSR-relevent salt systems, with the intent of supporting the development of the Molten Salt Thermal Properties Database (MSTDB). This database is jointly funded by the DOE-NE Nuclear Energy Advanced Modeling and Simulation Program and the MSR Campaign. Multiple DOE national laboratories, including Oak Ridge National Laboratory (ORNL), have been conducting measurements of thermophysical properties to support MSTDB development and provide MSR developers with access to new data that has been measured using modern methodologies and more advanced sample characterization techniques. These data may either fill gaps in the database or provide updated higher quality data to replace legacy data. Researchers at ORNL have recognized significant gaps in the transport property data of actinide-bearing fluoride salt systems of MSR industry interest. Moreover, for the data present in MSTDB in this category, the uncertainty margins are generally high, leading to questionability in our current understanding of the thermophysical characterization of actinide fluoride mixtures. As such, the focus of this study has been to generate new transport property data of actinide fluoride mixtures that are of immediate interest to MSR developers. Specifically, the mixtures NaF-UF 4 (78 - 22 mol%) and NaF-KF-UF 4 (57-16.04-26.91 mol%) have been studied—NaF-UF 4 for thermal conductivity and viscosity and NaF-KF-UF 4 for viscosity. Thermal conductivity measurements have been conducted with a variable gap apparatus, whereas viscosity has been measured with a rolling ball viscometer. Methodological and calibration details are provided for both measurement processes, along with measurement system updates that have enabled easier manufacturing of components and fewer challenges associated with conducting the measurements themselves. The resultant data collected for NaF-UF 4 (78–22 mol%) and NaF-KF-UF 4 (57-16.04-26.91 mol%) have been compared with relevant mixture data within the thermophysical arm of the MSTDB (MSTDB-TP).

22 GENERAL STUDIES OF NUCLEAR REACTORS↗
NASA NTRS1980

Actinide cosmic ray chronometers - Relative abundances and the cosmic ray lifetime

Measurements of ultraheavy cosmic rays will provide radioactive chronometers, including the actinides, which are expected to be present in the source. These primary chronometers differ from the Be-10 secondary chronometer in total inelastic cross-section and decay half-life. A propagation code, which includes nuclear fragmentation, radioactive decay, and ionization energy-loss of cosmic rays is being used to investigate the variations in the fluxes and mean ages which would be expected for various models of cosmic ray propagation. Some preliminary results in the actinide region are presented here which indicate that measurements of the relative abundances of the actinides in the cosmic rays will be very useful for understanding source abundances but less useful for studying propagation effects.

Margolis, S. H.↗
NASA NTRS1987

Actinide chemistry in Allende Ca-Al-rich inclusions

Fission track radiography is used to investigate the U and Th microscale distribution in a set of Allende-meteorite Ca-Al-rich inclusions. In the Type B inclusions, the major phases melilite and fassaite are important actinide host phases, and on the rims of Type B inclusions and throughout all other inclusions studied, perovskite is the dominant actinide host phase. Results suggest that neither alteration nor loss or gain of an actinide-rich phase appears to have been an important Th/U fractionation mechanism, and that volatility differences may be the dominant factor. Th/U and rare earth element abundance patterns for the spinel and perovskite rim suggest rim formation by volatilization of interior material, and within the constraints of the brief time scale required for this heating, several mechanisms for spinel-perovskite rim formation are possible.

Murrell, M. T.↗
NASA NTRS1993

Lanthanide and actinide chemistry at high C/O ratios in the solar nebula

Chemical equilibrium calculations were performed to study the condensation chemistry of the REE and actinides under the highly reducing conditions which are necessary for the formation of the enstatite chondrites. Our calculations confirm that the REE and actinides condensed into oldhamite (CaS), the major REE and actinide host phase in enstatite chondrites, at a carbon-oxygen (C/O) ratio not less than 1 in an otherwise solar gas. Five basic types of REE abundance patterns, several of which are analogous to REE abundance patterns observed in the Ca, Al-rich inclusions in carbonaceous chondrites, are predicted to occur in meteoritic oldhamites. All of the reported REE patterns in oldhamites in enstatite chondrites can be interpreted in terms of our condensation calculations. The observed patterns fall into three of the five predicted categories. The reported Th and U enrichments and ratios in meteoritic oldhamites are also consistent with predictions of the condensation calculations. Pure REE sulfides are predicted to condense in the 10 exp -6 to 10 exp -9 bar range and may be found in enstatite chondrites if they formed in this pressure range.

Lodders, Katharina↗
DOE OSTI2026

Covalency of M–N Bonds in Isomorphous Lanthanide and Actinide 5-(2-Pyridyl)-1H-tetrazolate Complexes

Experimental and computational analyses of [M(pdtz) 3 (H 2 O) 3 ]·3.5H 2 O (M 3+ = Pu 3+ −Cm 3+ , La 3+ −Nd 3+ , and Sm 3+ −Ho 3+ , pdtz− = 5-(2-pyridyl)-1H-tetrazolate) were conducted to understand potential differences in bonding between lanthanide and actinide complexes with a N-donor ligand. Structural analyses show that the An−N bond distances in the Pu 3+ , Am 3+ , and Cm 3+ complexes are within error of one another. Whereas in the lanthanide series, there is a nearly linear decrease in the Ln−N bond lengths from La 3+ to Ho 3+ (excluding Pm 3+ ). The An−N bond lengths are ∼0.015 Å shorter than their similarly-sized lanthanide analogs, in agreement with computational results that suggest greater covalent character in these bonds versus those with lanthanides. QTAIM analysis indicates that the An−N orbital mixing remains essentially unchanged from Pu 3+ to Cm 3+ , consistent with the nearly identical An−N bond lengths. However, upon deconvolution of the NLMOs into orbital compositions, the metal orbital contributions to An−N bonding decreases slightly overall wherein the 6d involvement remains constant, 7s involvement slightly increases, and 5f participation decreases. The molecular orbital energy diagram indicates that energy degeneracy between the 5f metal and 2p ligand orbitals increases from Pu 3+ to Cm 3+ and counteracts the contraction of the 5f orbtials. Together with prior reports of decreasing energy degeneracy between 5f and 3p orbitals from Np 3+ to Cf 3+ , these observations provide guidance on understanding how chemical bonding evolves in the actinide series.

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

Insights into the Complexation of Actinides by Diethylenetriaminepentaacetic Acid from Characterization of the Americium(III) Complex

Diethylenetriaminepentaacetic acid (DTPA) is a frequently used chelator in the nuclear and medical industries, especially for the complexation of trivalent actinides. However, structural data on these complexes in the solid-state have long remained elusive. Herein, a detailed structural analysis of the presented crystal structures of [C(NH 2 ) 3 ] 4 [Nd(DTPA)] 2 · n H 2 O and [C(NH 2 ) 3 ] 4 [Am(DTPA)] 2 · n H 2 O, where [C(NH 2 ) 3 ] + is guanidinium, details the subtle differences in the Lewis acidity between a lanthanide/actinide pair of similar ionic sizes. Contractions in nitrogen–metal bond lengths between neodymium(III) and americium(III) were observed, while the metal–oxygen bonds remained relatively consistent, highlighting the marginal favorability for actinide complexation over the lanthanides with moderately soft N-donors. Spectroscopic analysis shows significant splitting of many transitions and relatively strong electronic interactions with traditionally low-intensity transitions in the americium complex, as is demonstrated in the 7 F 0 → 7 F 5 transitions. Pressure-induced spectroscopic analysis showed surprisingly little effect on the americium complex, with 5 f →5 f transitions either not shifting or marginally shifting from 2 to 3 nm at 11.93 ± 0.06 GPa─atypical of a soft, N-donor americium complex under pressure. Finally, large voids occupied by water molecules in between the complexes within the crystal structure may be responsible for the lack of pressure response in the 5 f →5 f transitions.

absorption spectroscopy↗
DOE OSTI2025

Atomic Orbital Energy Matching vs Overlap in Actinide-Ligand Dative Bonding

Prebonding conditions and dative bond formation in actinide(IV)hexachloride complexes with U, Np, and Pu are studied by density functional theory (DFT) calculations, focusing on the interplay of atomic orbital (AO) overlap and AO energy matching in the formation of molecular orbitals (MOs) and the subsequent identification of dative bonds. The extent of donation is tracked via population analysis, MO localization, and bond-order criteria. DFT Fock matrices are used to setup models in which varying numbers of valence AOs interact to form dative bonds. The results confirm, among other effects, a contribution to metal−ligand covalency from the actinide (An) 6p shell. Better matching of An(5f) and Cl(3p) energies occurs as the An(5f) level stabilizes with increasing An effective nuclear charge. A near-degeneracy occurs in the case of the α-spin orbitals of the Pu system, but it is inconsequential. Altogether, better AO energy matching for An(5f) and Cl(3p) along the series U, Np, Pu is counter-balanced by decreasing AO overlap and decreasing availability of 5f acceptor orbitals, leading to similar bond orders and extents of donation in the three systems.

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

Fabrication and Evaluation of Large Alumina Crucibles by Vat Photopolymerization Additive Manufacturing for High-Temperature Actinide Chemistry

Additive manufacturing (AM) offers opportunities to advance the design and function of ceramic tooling in high temperature actinide pyrochemistry. In technical ceramics such as alumina, conventional forming techniques often restrict design flexibility and can limit experimental progress. In this study, we investigate the use of vat photopolymerization (VP) with commercial resins to fabricate large-scale alumina crucibles, reaching dimensions up to 125 mm, which is significantly larger than typically reported for dense VP ceramics. Notably, these additively manufactured components are produced using consumer-grade hardware, which limits process control, but offers significant upside in scalability and accessibility. Using microscopy and X-ray computed tomography, the VP alumina parts have high bulk densities above 95%, but also the prevalence of AM-induced artifacts and surface defects. Mechanical testing showed these defects to significantly reduce flexural strength and compromise part reliability. Electrorefining trials under sustained exposure to molten salts and metals reveal mixed results, with the AM material exhibiting high chemical compatibility, but mechanical failures due to the reduced strength were prevalent. Our findings illustrate both the promise and current limitations of AM ceramics for actinide chemistry, and point toward future improvements in process optimization, design strategies, and part screening to enhance performance and reliability.

Materials science↗
DOE OSTI2024

Purification Techniques for Actinide Radiolysis Studies

Our fundamental understanding of actinide radiation-induced redox chemistry is crucial due to their unavoidable exposure to ionizing radiation fields, both inherent and from in-process applications. Plutonium (Pu) and americium (Am) both possess multiple oxidation states, the careful manipulation of which are essential in the study and utilization of their rich chemistry, developing new technologies, and securing the long-term sustainability of nuclear power. However, knowledge in this area is far from complete. We have studied the radiation-induced chemistry of both Pu and Am through a variety of techniques, including gamma irradiation, in-situ alpha irradiation and pulse radiolysis experiments. However, for the collection of accurate data, thorough purification and quantification of actinide-containing solutions is required. This presentation will cover the purification and quantification techniques employed for the radiolysis experiments described in our recent publications: Kynman et al., Multiscale Modeling of Plutonium Radiation Chemistry in Nitric Acid Solutions. 1. Cobalt-60 Gamma Irradiation of Pu(IV) [https://pubs.acs.org/doi/10.1021/acs.inorgchem.4c00138] and Kynman et al., Generation and Study of Am(IV) by Temperature-Controlled Electron Pulse Radiolysis [https://doi.org/10.1039/D4DT00991F].

38 RADIATION CHEMISTRY, RADIOCHEMISTRY, AND NUCLEA↗
DOE OSTI2024

LDRD poster - Identifying the speciation of salt-based actinides in the presence of contaminants

Molten salt reactors (MSRs) are among the most promising Generation IV nuclear reactors. The salts used in these reactors exhibit a high affinity for moisture and oxygen, and heating does not eliminate the oxides that are formed. Additionally, due to the high operating temperatures, reactor parts experience pronounced corrosion, and the resulting corrosion products integrate into the fuel salt system. It is hypothesized that the speciation of f-elements in molten salts would change in the presence of oxides and corrosion products. These changes in local structure can alter the rheological properties, which are critical to the operational and safety parameters of the reactors. Therefore, an in-depth understanding of how corrosion products influence lanthanide/actinide speciation is crucial. To test this hypothesis, lanthanides (as surrogates for actinides) and actinide chlorides were mixed with oxides (such as nickel oxide and lithium oxide) and/or corrosion products (e.g., nickel chloride) and reacted in molten salts. The resulting phases were analyzed using techniques such as powder X-ray diffraction, Raman spectroscopy, UV-Visible spectroscopy, and nuclear magnetic resonance spectroscopy. In the presence of oxides, due to the high oxophilicity of f-elements, these elements capture oxygen from the oxides, forming lanthanide/actinide oxide or oxychloride phases. Specifically, with cerium chloride, the introduction of lithium oxide to the formation of various final products depending on the oxide concentration. At lower oxide concentrations, cerium oxychloride (CeOCl) in the +3 oxidation state was observed, while an increase in the oxide concentration led to the formation of cerium dioxide (CeO2), where cerium is in the +4 oxidation state. In contrast, with nickel oxide, CeOCl formation was consistently observed, regardless of the oxide concentration. This project successfully determined that the speciation of f-elements change in the presence of oxides and different oxides in molten salts result in different final products. When the influence of nickel chloride was examined, changes in f-element speciation were not observed. However, it reacted with lithium chloride to generate a lithium-nickel-chloride (Li6NiCl8) phase, which was also observed when nickel oxide was reacted. Computational models were developed to simulate the phases anticipated under experimental conditions.

37 - INORGANIC, ORGANIC, PHYSICAL AND ANALYTICAL C↗
DOE OSTI2025

Ligand‐Directed Actinide Oxo‐Bond Manipulation in Actinyl Thiacalix[4]arene Complexes

Abstract Understanding the chemistry of the inert actinide oxo bond in actinyl ions AnO 2 2+ is important for controlling actinide behavior in the environment, during separations, and in nuclear waste (An=U, Np, Pu). The thioether calixarene TC4A (4‐ tert ‐butyltetrathiacalix[4]arene) binds equatorially to the actinyl cation forming a conical pocket that differentiates the two trans‐ oxo groups. The ‘ate’ complexes, [A] 2 [UO 2 (TC4A)] (A=[Li(DME) 2 ], HNEt 3 ) and [HNEt 3 ] 2 [AnO 2 (TC4A)] (An=U, Np, Pu), enable selective oxo chemistry. Silylation of the U VI oxo groups by bis(trimethylsilyl)pyrazine occurs first at only the unencapsulated exo oxo and only one silylation is needed to enable migration of the endo oxo out of the cone, whereupon a second silylation affords the stable U IV cis‐ bis(siloxide) [A] 2 [U(OSiMe 3 ) 2 (TC4A)]. Calculations confirm that only one silylation event is needed to initiate oxo rearrangement, and that the putative cis dioxo isomer of [UO 2 (TC4A)] 2− would be stable if it could be accessed synthetically, at only 23 kcal.mol −1 in energy above the classical trans dioxo. Calculations for the transuranic cis [AnO 2 (TC4A)] 2− (An=Np, Pu) are at higher energies, 30–35 kcal.mol −1 , retaining the U complexes as the more obvious target for a cis ‐dioxo actinyl ion. The aryloxide (OAr) groups of the macrocycle are essential in stabilizing this as‐yet unseen uranyl geometry as further bonding in the TC4A U‐O Ar groups stabilizes the U=O ‘yl’ bonds, explaining the stability of the putative cis [UO 2 (TC4A)] 2− in this ligand framework.

Pyrch, Mikaela M. [College of Chemistry University↗
DOE OSTI2025

Ligand‐Directed Actinide Oxo‐Bond Manipulation in Actinyl Thiacalix[4]arene Complexes

Understanding the chemistry of the inert actinide oxo bond in actinyl ions AnO2 2+ is important for controlling actinide behavior in the environment, during separations, and in nuclear waste (An=U, Np, Pu). The thioether calixarene TC4A (4-tert-butyltetrathiacalix[4]arene) binds equatorially to the actinyl cation forming a conical pocket that differentiates the two trans-oxo groups. The 'ate' complexes, [A]2[UO2(TC4A)] (A=[Li(DME)2], HNEt3) and [HNEt3]2[AnO2(TC4A)] (An=U, Np, Pu), enable selective oxo chemistry. Silylation of the UVI oxo groups by bis(trimethylsilyl)pyrazine occurs first at only the unencapsulated exo oxo and only one silylation is needed to enable migration of the endo oxo out of the cone, whereupon a second silylation affords the stable UIV cis-bis(siloxide) [A]2[U(OSiMe3)2(TC4A)]. Calculations confirm that only one silylation event is needed to initiate oxo rearrangement, and that the putative cis dioxo isomer of [UO2(TC4A)]2- would be stable if it could be accessed synthetically, at only 23 kcal.mol-1 in energy above the classical trans dioxo. Calculations for the transuranic cis[AnO2(TC4A)]2- (An=Np, Pu) are at higher energies, 30-35 kcal.mol-1, retaining the U complexes as the more obvious target for a cis-dioxo actinyl ion. The aryloxide (OAr) groups of the macrocycle are essential in stabilizing this as-yet unseen uranyl geometry as further bonding in the TC4A U-OAr groups stabilizes the U=O 'yl' bonds, explaining the stability of the putative cis[UO2(TC4A)]2- in this ligand framework.

Pyrch, Mikaela M↗
DOE OSTI2025

Shell effects in quasi-fission: Reactions forming actinide and superheavy compound nuclei

Quasi-fission occurs in fully damped heavy-ion collisions following a significant mass transfer between the fragments, without formation of a compound nucleus. As in fission, quasi-fission is expected to be affected by quantum effects leading to asymmetric mass splits. Quantum shells stabilising fission fragments with octupole shapes have been invoked as a factor determining the distribution of nucleons between the fragments at scission, explaining the fact that the centroid of the heavy fragment charge distribution is found around Z = 54 protons in fission and quasi-fission of actinides. These shell effects are studied in microscopic studies of quasi-fission. In particular, time-dependent Hartree-Fock (TDHF) calculations have been performed for reactions forming actinides.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗
DOE OSTI2025

Actinide 5f Occupations: The Case of PuO 2

In actinide chemistry, the formal number of open-shell 5f electrons, n open , is a well-defined quantity with an integer value. The effective 5f occupation, n f , additionally takes donation and back-donation into account, generally has a non-integer value, and has varying numerical definitions. The present study explores the important distinction between n f and n open in actinide chemistry with the example of PuO2, by using electronic structure methods with a relativistic Hamiltonian in combination with experimental Pu M 5 -edge high-energy-resolution X-ray absorption and emission spectroscopic data. The total donation to the metal in PuO 2 is between 3.1 and 2.4 electrons, depending on the type of calculation, most of which is to the Pu 6d and 5f shells. The donation into 5f is sensitive to the approximations in the electronic structure model but likely amounts to 1.6/0.8 electrons when the diffuse regions of the 5f shell are included/excluded. Valence band resonant inelastic X-ray scattering experiments demonstrate that Pu 5f electron density is present in the valence band; thus, there is a clear experimental signature of covalent bonding in PuO 2 . Pu M 5 -edge and M 3 -edge high-energy-resolution X-ray absorption near-edge structures for Pu 3+ and Pu 4+ in an aqueous solution are compared to PuO 2 , showing that Pu in PuO 2 has an nf closer to Pu 4+ (aq).

37 INORGANIC, ORGANIC, PHYSICAL, AND ANALYTICAL CH↗
DOE OSTI2026

Back to Basics: Lanthanide and Heavy Actinide Chelation at High pH by Niobium Polyoxometalates

Niobium polyoxometalates (Nb-POMs) form in alkaline media, which limits their use as ligands for acidic cations, particularly lanthanides and actinides. Metal-Nb-POM moieties have the potential for emergent and enhanced properties, based on strong complexation behavior and high stability of the resultant materials. Here, in this study, we probe interactions of lanthanides (Pr 3+ , Nd 3+ , Sm 3+ , Eu 3+ , Tb 3+ , Dy 3+ ) and actinides (Am 3+ , Cm 3+ ) with a Nb-POM [Nb 6 O 19 ] 8– (Nb 6 ) in alkaline media. Nb 6 , the most charge-dense Nb-POM, enhances f-element luminescence emission by up to × 10 6 , via Nb-POM-mediated sensitization. Lengthened emission lifetimes correlate with the release of the metal-cation hydration sphere, replaced by multidentate Nb-POMs. The Nb 6 –Ln(An) complexes resist carbonate and phosphate displacement, and Nb 6 –Ln(An) complexation is retained upon isolation of the solids from solution. Electrospray ionization mass spectrometry (ESI-MS) and Raman spectroscopy both indicate the formation of the unprecedented Peacock–Weakley Nb-POM ([LnIII(Nb 5 O 18 ) 2 ] 19- ) in addition to simple Nb 6 –Ln coordination complexes. Luminescence emission spectra support the presence of simple Nb 6 –Ln coordination complexes. Small-angle X-ray scattering (SAXS) evidence the formation of Ln-Nb-POM aggregates. This foundational investigation highlights the potential of Nb-POMs as metal–ligands at basic pH, with value-added properties including scaffolding extended materials and controlling light absorption and emission.

organic↗
DOE OSTI2025

Expanding on the ability of trivalent actinides to support microbial alcohol metabolism in evolved methylotrophic bacterium

The 4 f elements, known as the lanthanides, have only recently been recognized as biologically essential metals. These elements can be found in the active site of certain alcohol dehydrogenase (ADH) enzymes, which are used by methylotrophic bacteria to metabolize simple alcohols such as methanol and ethanol. The 5 f elements, known as the actinides, often show similar chemical behaviour to the lanthanides and recent reports demonstrated that americium (Am) and curium (Cm) can replace lanthanides in certain ADHs to yield a catalytically competent enzyme and support bacterial life. In this work, we expand on these results to show the trivalent ions actinium (Ac3+), americium (Am3+), curium (Cm3+), berkelium (Bk3+), and californium (Cf3+) all support growth of an evolved strain of the model methylotroph Methylobacterium extorquens AM1. Further in vitro experiments using a reconstituted ethanol dehydrogenase enzyme confirm the ability of this enzyme to utilize trivalent actinide ions.

Woods, Joshua J↗
DOE OSTI2026

Actinide complexes with Wells–Dawson polyoxometalates (part 1): americium and curium

We report the first trivalent actinide complexes with a Wells–Dawson polyoxometalate. Americium(III) forms two distinct phases: triclinic K 17 Am(P 2 W 17 O 61 ) 2 ·42.5H 2 O and monoclinic K 17 Am(P 2 W 17 O 61 ) 2 ·12H 2 O. Curium(III) crystallizes as monoclinic K 17 Cm(P 2 W 17 O 61 ) 2 ·8H 2 O. XRD-quality single crystals were obtained from just ∼330 nanograms of actinides. This work establishes clear structure–property relationships that will guide investigations on scarce f-elements.

and nuclear chemistry↗
DOE OSTI2026

Muon-induced fission of actinide nuclei

A negative muon captured by an actinide cascades down through the muonic atomic levels; deeply bound transitions can proceed via inverse internal conversion, depositing the muonic transition energy directly into the nucleus and, when the deposited energy exceeds the fission barrier, inducing prompt fission. Because the muon mean lifetime exceeds the saddle-to-scission timescale by orders of magnitude, the muon can survive the entire fission event as a 1⁢𝑠 spectator and ultimately attach to one or both of the emerging fragments. Its postscission attachment probability to the light fragment, 𝑃 𝐿 , can be used as a direct electromagnetic probe of fission dynamics on a timescale of 10 −21 s. In previous work, we introduced a three-dimensional lattice solution of the time-dependent Dirac equation coupled to the electromagnetic field generated by a fissioning nucleus and reported 𝑃 𝐿 for several actinides at a single dissipation strength. In this work, we extend that framework to a systematic survey of 232 Th , 238 U , and 240 Pu and implement a more realistic fission model which incorporates dynamic pairing correlations. We find that 𝑃 𝐿 falls steeply with the fragment charge asymmetry, a robust structural fingerprint of the fissioning system, while its dependence on nuclear dissipation is secondary and sensitive to the phenomenological friction prescription. These results establish 𝑃 𝐿 as a clean electromagnetic probe of fragment charge asymmetry and motivate a self-consistent, coordinate- and time-dependent treatment of nuclear dissipation as the natural next step.

73 NUCLEAR PHYSICS AND RADIATION PHYSICS↗