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1. Benchmarking embedded chain breaking in quantum annealing ^*

   https://doi.org/10.1088/2058-9565/ac26d2  

   Thinh V. Le, Manh V. (March 2022, Quantum Science and Technology)

   Abstract Quantum annealing solves combinatorial optimization problems by finding the energetic ground states of an embedded Hamiltonian. However, quantum annealing dynamics under the embedded Hamiltonian may violate the principles of adiabatic evolution and generate excitations that correspond to errors in the computed solution. Here we empirically benchmark the probability of chain breaks and identify sweet spots for solving a suite of embedded Hamiltonians. We further correlate the physical location of chain breaks in the quantum annealing hardware with the underlying embedding technique and use these localized rates in a tailored post-processing strategies. Our results demonstrate how to use characterization of the quantum annealing hardware to tune the embedded Hamiltonian and remove computational errors. 

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2. Electron-Transfer Chain Catalysis of η ² -Arene, η ² -Alkene, and η ² -Ketone Exchange on Molybdenum

   https://doi.org/10.1021/acscatal.9b04191  

   Dakermanji, Steven J.; Smith, Jacob A.; Westendorff, Karl S.; Pert, Emmit K.; Chung, Andrew D.; Myers, Jeffery T.; Welch, Kevin D.; Dickie, Diane A.; Harman, W. Dean (October 2019, ACS Catalysis)
3. Influence of Peripheral and Ancillary Changes on the Electron Transport of ^HS 3d ⁵ Fe ^III Metallosurfactants – Substituents, Chain Length, Subphase Polarity, and Junction Electrodes

   https://doi.org/10.1021/acs.jpcc.4c02249  

   Kirui, Gibson; Kaushalya, Widana; Perera, S Sameera; Walker, Alice R; Verani, Cláudio N (June 2024, The Journal of Physical Chemistry C)
4. Magnetically Driven Quantum Phase Transition in a Low-Dimensional Pyrazine-Bridged Cu ²⁺ Chain Magnet

   https://doi.org/10.1021/acs.inorgchem.5c00458  

   Blockmon, Avery L; Jo, Jinhyeong; Park, Kiman; Kirkman-Davis, Emma; Turnbull, Mark M; Lee, Minseong; Singleton, John; McGill, Stephen A; Kim, Heung-Sik; Lee, Jun Hee; et al (June 2025, Inorganic Chemistry)

   The magnetic properties and phase diagrams of S = 1/2 quasi-one-dimensional Heisenberg antiferromagnets are well established with copper-containing coordination polymers as the platform of choice due to their low energy scales and ease of chemical substitution. The inability to uncover orbitally resolved components of the magnetization has, however, been a longstanding barrier to greater understanding of high field spin state transitions. In this work, we combine pulsed field magnetization, optical spectroscopy, and magnetic circular dichroism with complementary electronic structure calculations to unravel orbital-specific contributions to the magnetism in the linear chain quantum magnet [CuL2(H2O)2(pyz)](ClO4)2 [L = 5-methyl-2-pyridone; pyz = pyrazine]. In addition to revealing a spin flop and field-driven transition to the fully saturated spin state, we untangle the green → teal color change across the 185 K structural phase transition and employ what we learn about the different Cu2+ → pyrazine charge transfer excitations to decompose the magnetic circular dichroism. Analysis reveals that both eg-derived Cu2+ 3d orbitals play a role in the field-driven transition to the fully saturated state, not just those formally hosting unpaired electrons. We attribute the surprisingly strong dichroic signature at room temperature to the presence of uncorrelated spin. 

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5. Immobilized ¹³ C-labeled polyether chain ends confined to the crystallite surface detected by advanced NMR

   https://doi.org/10.1126/sciadv.abc0059  

   Yuan, Shichen; Schmidt-Rohr, Klaus (September 2020, Science Advances)

   null (Ed.)

   A comprehensive 13 C nuclear magnetic resonance (NMR) approach for characterizing the location of chain ends of polyethers and polyesters, at the crystallite surface or in the amorphous layers, is presented. The OH chain ends of polyoxymethylene are labeled with 13 COO-acetyl groups and their dynamics probed by 13 C NMR with chemical shift anisotropy (CSA) recoupling. At least three-quarters of the chain ends are not mobile dangling cilia but are immobilized, exhibiting a powder pattern characteristic of the crystalline environment and fast CSA dephasing. The location and clustering of the immobilized chain ends are analyzed by spin diffusion. Fast 1 H spin diffusion from the amorphous regions shows confinement of chain ends to the crystallite surface, corroborated by fast 13 C spin exchange between chain ends. These observations confirm the principle of avoidance of density anomalies, which requires that chains terminate at the crystallite surface to stay out of the crowded interfacial layer. 

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