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1. Relevance of the Nuclear Structure of the Stable Ge Isotopes to the Neutrino-less Double-Beta Decay of ⁷⁶ Ge

   https://doi.org/10.1051/epjconf/202023204011  

   Yates, S. W.; Peters, E. E.; Crider, B. P.; Mukhopadhyay, S.; Ramirez, A. P.; Mitchell, A.J.; Pavetich, S.; Koll, D. (January 2020, EPJ Web of Conferences)

   Gamma-ray detection following the inelastic neutron scattering reaction on isotopically enriched material was used to study the nuclear structure of 74 Ge. From these measurements, low-lying, low-spin excited states were characterized, new states and their decays were identified, level lifetimes were measured with the Doppler-shift attenuation method (DSAM), multipole mixing ratios were established, and transition probabilities were determined. New structural features in 74 Ge were identified, and the reanalysis of older 76 Ge data led to the placement of the 2 + member of the intruder band. In addition, a number of previously placed states in 74 Ge were shown not to exist. A procedure for future work, which will lead to meaningful data for constraining calculations of the neutrinoless double-beta decay matrix element, is suggested. 

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2. Core excitation in ⁹² Mo up to high spin

   https://doi.org/10.1088/1361-6471/ad9343  

   Malik, Vishal; Palit, R; Srivastava, P C; Dey, P; Patel, Deepak; Das, Biswajit; Negi, D; Garg, U; Raut, R; Goel, Nidhi; et al (December 2024, Journal of Physics G: Nuclear and Particle Physics)

   Abstract An in-beam gamma-ray spectroscopy study of the even–even nucleus⁹²Mo has been carried out using the³⁰Si +⁶⁵Cu,¹⁸O +⁸⁰Se reactions at beam energies of 120 and 99 MeV, respectively. Angular distribution from the oriented state ratio (R_ADO) and linear polarization (Δ_asym) measurements have fixed most of the tentatively assigned spin-parity of the high-energy levels. A large-scale shell-model calculation using the GWBXG interaction has been carried out to understand the configuration and structure of both positive and negative parity states up to the highest observed spin. The high-spin states primarily originate from the coupling of excited proton- and neutron-core structures in an almost stretched manner. The systematics of the energy required to form a neutron particle-hole pair excitation,νg_9/2→νd_5/2, is discussed. The lifetimes of a few high-spin states have been measured using the Doppler shift attenuation method. Additionally, a qualitative argument is proposed to explain the comparatively strong E1 transition feeding the 7310.9 keV level. 

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3. Spin dynamics of [1,2- ¹³ C ₂ ]pyruvate hyperpolarization by parahydrogen in reversible exchange at micro Tesla fields

   https://doi.org/10.1039/d3cp00843f  

   Browning, Austin; Macculloch, Keilian; TomHon, Patrick; Mandzhieva, Iuliia; Chekmenev, Eduard Y.; Goodson, Boyd M.; Lehmkuhl, Sören; Theis, Thomas (June 2023, Physical Chemistry Chemical Physics)

   Hyperpolarization of 13 C-pyruvate via Signal Amplificaton By Reversibble Exchange (SABRE) is an important recent discovery because of both the relative simplicity of hyperpolarization and the central biological relevance of pyruvate as a biomolecular probe for in vitro or in vivo studies. Here, we analyze the [1,2- 13 C 2 ]pyruvate-SABRE spin system and its field dependence theoretically and experimentally. We provide first-principles analysis of the governing 4-spin dihydride- 13 C 2 Hamiltonian and numerical spin dynamics simulations of the 7-spin dihydride- 13 C 2 –CH 3 system. The analytical and the numerical results are compared to matching systematic experiments. With these methods we unravel the observed spin state mixing of singlet states and triplet states at microTesla fields and we also analyze the dynamics during transfer from micro-Tesla field to high field for detection to understand the resulting spectra from the [1,2- 13 C 2 ]pyruvate-SABRE system. 

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4. Probing Redox Non‐Innocence in Iron–Carbene Complexes {Fe=C(H)Ar} ^10–11 by ^1,2 H and ¹³ C Pulse Electron Paramagnetic Resonance

   https://doi.org/10.1002/anie.202110704  

   Arnett, Charles H.; Oyala, Paul H.; Agapie, Theodor (November 2021, Angewandte Chemie International Edition)

   Abstract We report the synthesis and spectroscopic characterization of a series of iron‐carbene complexes in redox states {Fe=C(H)Ar}^10–11. Pulse EPR studies of the^1,2H and¹³C isotopologues of {Fe=C(H)Ar}¹¹reveal the high covalency of the Fe–carbene bonding, leading to a more even spin distribution than commonly observed for reduced Fischer carbenes. 

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5. First detection and analysis of an electronic spectrum of vanadium hydride: The D ⁵ Π –X ⁵ Δ (0,0) band

   https://doi.org/10.1063/5.0105844  

   Varberg, Thomas D. (August 2022, The Journal of Chemical Physics)

   The D 5 Π–X 5 Δ (0,0) band of vanadium hydride at 654 nm has been recorded by laser excitation spectroscopy and represents the first analyzed spectrum of VH in the gas phase. The molecules were generated using a hollow cathode discharge source, with laser-induced fluorescence detected via the D 5 Π–A 5 Π (0,0) transition. All five main (ΔΩ = ΔΛ) subbands were observed as well as several satellite ones, which together create a rather complex and overlapped spectrum covering the region 15 180–15 500 cm −1 . The D 5 Π state displays the effects of three strong local perturbations, which are likely caused by interactions with high vibrational levels of the B 5 Σ − and c 3 Σ − states, identified in a previous multiconfigurational self-consistent field study by Koseki et al. [J. Phys. Chem. A 108, 4707 (2004)]. Molecular constants describing the X 5 Δ, A 5 Π, and D 5 Π states were determined in three separate least-squares fits using effective Hamiltonians written in a Hund’s case (a) basis. The fine structure of the ground state is found to be consistent with its assignment as a σπ 2 δ, 5 Δ electronic state. The fitted values of its first-order spin–orbit and rotational constants in the ground state are [Formula: see text] and B = 5.7579(13) cm −1 , the latter of which yields a bond length of [Formula: see text] Å. This experimental value is in good agreement with previous computational studies of the molecule and fits well within the overall trend of decreasing bond length across the series of 3d transition metal monohydrides. 

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