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We report the first tris(alkoxide)V(iii) complex to bind dinitrogen. Removal of THF from V(OR)3THF furnishes the highly reactive V(OR)3fragment, which binds dinitrogen to form [V(OR)3]2(μ-N2) in the solid state. Dinitrogen is readily released upon dissolution of the complex. Structural and DFT studies are consistent with significant activation of N2when bound by the vanadium tris(alkoxide) platform. [ABSTRACT FROM AUTHOR]

The misfit layer compounds (BiSe)1.23CrSe2 (I) and (BiSe)1.22(Cr1.2Se2)2 (II) are prepared by solid state reaction of Bi2Se3 and Cr2Se3 (C-coated evacuated silica tubes, 780 °C, 165 h; controlled cooling). [ABSTRACT FROM AUTHOR]

We report a vanadium complex in a nuclear-spin free ligand field that displays two key properties for an ideal candidate qubit system: long coherence times that persist at high temperature, T2 = 1.2 /μs at 80 K, and the observation of quantum coherences from multiple transitions. The electron paramagnetic resonance (EPR) spectrum of the complex [V(C8S8)3]2- displays multiple transitions arising from a manifold of states produced by the hyperfine coupling of the S = l/2 electron spin and I = 7/2 nuclear spin. Transient nutation experiments reveal Rabi oscillations for multiple transitions. These observations suggest that each pair of hyperfine levels hosted within [V(C8S8)3]2- are candidate qubits. The realization of multiple quantum coherences within a transition metal complex illustrates an emerging method of developing scalability and addressability in electron spin qubits. This study presents a rare molecular demonstration of multiple Rabi oscillations originating from separate transitions. These results extend observations of multiple quantum coherences from prior reports in solid-state compounds to the new realm of highly modifiable coordination compounds. [ABSTRACT FROM AUTHOR]

Exploration beyond the known phase space of thermodynamically stable compounds into the realm of metastable materials is a frontier of materials chemistry. The application of high pressure in experiment and theory provides a powerful vector by which to explore this uncharted phase space, allowing discovery of complex new structures and bonding in the solid state. We harnessed this approach for the Cu-Bi system, where the realization of new phases offers potential for exotic properties such as superconductivity. This potential is due to the presence of bismuth, which, by virtue of its status as one of the heaviest stable elements, forms a critical component in emergent materials such as superconductors and topological insulators. To fully investigate and understand the Cu-Bi system, we welded theoretical predictions with experiment to probe the Cu-Bi system under high pressures. By employing the powerful approach of in situ X-ray diffraction in a laser-heated diamond anvil cell (LHDAC), we thoroughly explored the high-pressure and high-temperature (high-PT) phase space to gain insight into the formation of intermetallic compounds at these conditions. We employed density functional theory (DFT) calculations to calculate a pressure versus temperature phase diagram, which correctly predicts that CuBi is stabilized at lower pressures than Cu11Bi7, and allows us to uncover the thermodynamic contributions responsible for the stability of each phase. Detailed comparisons between the NiAs structure type and the two high-pressure Cu-Bi phases, Cu11Bi7 and CuBi, reveal the preference for elemental segregation within the Cu-Bi phases, and highlight the unique channels and layers formed by ordered Cu vacancies. The electron localization function from DFT calculations account for the presence of these "voids" as a manifestation of the lone pair orientation on the Bi atoms. Our study demonstrates the power of joint experimental-computational work in exploring the chemistry occurring at high-PT conditions. The existence of multiple high-pressure-stabilized phases in the Cu-Bi binary system, which can be readily identified with in situ techniques, offers promise for other systems in which no ambient pressure phases are known to exist. [ABSTRACT FROM AUTHOR]

The realization of quantum information processing would disrupt the status quo in the realm of computation; the extraordinary power of a hypothetical quantum computer motivates significant research efforts toward creating such a device. One promising route to enable quantum information processing involves employing electronic spins as the elementary unit of information, known as a qubit. Within this paradigm, paramagnetic defect sites in solid-state materials demonstrate appreciable promise, and recent developments in paramagnetic molecular coordination complexes illustrate an encouraging trajectory. While solid-state systems exhibit long spin coherence lifetimes, rational control of their properties remains challenging. Effecting synthetic control over qubit design prompted the study of tunable molecular species to develop design principles for spin coherence lifetimes. The challenge now lies in extending those molecular design principles to target new solid-state architectures that could enable device-scale systems. In this perspective, we detail recent progress in the rational design of molecular qubit complexes and highlight the advances that will be necessary in order to apply that progress to solid-state systems. We further examine the impact that the lessons learned from the study of qubits can have in the related fields of magnetic resonance imaging and biological sensing. [ABSTRACT FROM AUTHOR]