Probing Vibrational Symmetry Effects and Nuclear Spin Economy Principles in Molecular Spin Qubits.

The selection of molecular spin qubits with a long coherence time, Tm, is a central task for implementing molecule-based quantum technologies. Even if a sufficiently long Tm can be achieved through an efficient synthetic strategy and ad hoc experimental measurement procedures, many factors contributing to the loss of coherence still need to be thoroughly investigated and understood. Vibrational properties and nuclear spins of hydrogens are two of them. The former plays a paramount role, but a detailed theoretical investigation aimed at studying their effects on the spin dynamics of molecular complexes such as the benchmark phthalocyanine (Pc) is still missing, whereas the effect of the latter deserves to be examined in detail for such a class of compounds. In this work, we adopted a combined theoretical and experimental approach to investigate the relaxation properties of classical [Cu(Pc)] and a CuII complex based on the ligand tetrakis(thiadiazole)porphyrazine (H2TTDPz), characterized by a hydrogen-free molecular structure. Systematic calculations of molecular vibrations exemplify the effect of normal modes on the spin-lattice relaxation process, unveiling a different contribution to T1 depending on the symmetry of normal modes. Moreover, we observed that an appreciable Tm enhancement could be achieved by removing hydrogens from the ligand.

Radiofrequency to Microwave Coherent Manipulation of an Organometallic Electronic Spin Qubit Coupled to a Nuclear Qudit.

We report here a comprehensive characterization of a 3d organometallic complex, [V(Cp)2Cl2] (Cp = cyclopentadienyl), which can be considered as a prototypical multilevel nuclear qudit (nuclear spin I = 7/2) hyperfine coupled to an electronic qubit (electronic spin S = 1/2). By combining complementary magnetic resonant techniques, such as pulsed electron paramagnetic resonance (EPR) and broadband nuclear magnetic resonance (NMR), we extensively characterize its Spin Hamiltonian parameters and its electronic and nuclear spin dynamics. Moreover, we demonstrate the possibility to manipulate the qubit-qudit multilevel structure by resonant microwave and radiofrequency pulses, driving coherent Rabi oscillations between targeted electronuclear states. The obtained results demonstrate that this simple complex is a promising candidate for quantum computing applications.

First-Principles Investigation of Spin-Phonon Coupling in Vanadium-Based Molecular Spin Quantum Bits.

Paramagnetic molecules can show long spin-coherence times, which make them good candidates as quantum bits (qubits). Reducing the efficiency of the spin-phonon interaction is the primary challenge toward achieving long coherence times over a wide temperature range in soft molecular lattices. The lack of a microscopic understanding about the role of vibrations in spin relaxation strongly undermines the possibility of chemically designing better-performing molecular qubits. Here we report a first-principles characterization of the main mechanism contributing to the spin-phonon coupling for a class of vanadium(IV) molecular qubits. Post-Hartree-Fock and density functional theory methods are used to determine the effect of both intermolecular and intramolecular vibrations on modulation of the Zeeman energy for four molecules showing different coordination geometries and ligands. This comparative study provides the first insight into the role played by coordination geometry and ligand-field strength in determining the spin-lattice relaxation time of molecular qubits, opening an avenue to the rational design of new compounds.

Quantum Coherence Times Enhancement in Vanadium(IV)-based Potential Molecular Qubits: the Key Role of the Vanadyl Moiety.

In the search for long-lived quantum coherence in spin systems, vanadium(IV) complexes have shown record phase memory times among molecular systems. When nuclear spin-free ligands are employed, vanadium(IV) complexes can show at low temperature sufficiently long quantum coherence times, Tm, to perform quantum operations, but their use in real devices operating at room temperature is still hampered by the rapid decrease of T1 caused by the efficient spin-phonon coupling. In this work we have investigated the effect of different coordination environments on the magnetization dynamics and the quantum coherence of two vanadium(IV)-based potential molecular spin qubits in the solid state by introducing a unique structural difference, i.e., an oxovanadium(IV) in a square pyramidal versus a vanadium(IV) in an octahedral environment featuring the same coordinating ligand, namely, the 1,3-dithiole-2-thione-4,5-dithiolate. This investigation, performed by a combined approach of alternate current (ac) susceptibility measurements and continuous wave (CW) and pulsed electron paramagnetic resonance (EPR) spectroscopies revealed that the effectiveness of the vanadyl moiety in enhancing quantum coherence up to room temperature is related to a less effective mechanism of spin-lattice relaxation that can be quantitatively evaluated by the exponent n (ca. 3) of the temperature dependence of the relaxation rate. A more rapid collapse is observed for the non-oxo counterpart (n = 4) hampering the observation of quantum coherence at room temperature. Record coherence time at room temperature (1.04 µs) and Rabi oscillations are also observed for the vanadyl derivative in a very high concentrated material (5 ± 1%) as a result of the additional benefit provided by the use of a nuclear spin-free ligand.

The chimera of 2D- and 1D-graphene magnetization by hydrogenation or fluorination: critically revisiting old schemes and proposing new ones by ab initio methods.

Graphene is an ideal candidate material for spintronics due to its layered structure and peculiar electronic structure. However, in its pristine state, the production of magnetic moments is not trivial. A very appealing approach is the chemical modification of pristine graphene. The main obstacle is the control of the geometrical features and the selectivity of functional groups. The lack of a periodic functionalization pattern of the graphene sheet prevents, therefore, the achievement of long-range magnetic order, thus limiting its use in spintronic devices. In such regards, the stability and the magnitude of the instilled magnetic moment depending on the size and shape of in silico designed graphane islands and ribbons embedded in graphene matrix will be computed and analysed. Our findings thus suggest that a novel and magneto-active graphene derivative nanostructure could become achievable more easily than extended graphone or nanoribbons, with a strong potential for future spintronics applications with a variable spin-current density.

An exchange coupled meso-meso linked vanadyl porphyrin dimer for quantum information processing.

We report here the synthesis of a new meso-meso (m-m) singly linked vanadyl-porphyrin dimer that crystallizes in two different pseudo-polymorphs. The single crystal continuous-wave electron paramagnetic resonance investigation evidences a small but crucial isotropic exchange interaction, J, between the two tilted, and thus distinguishable, spin centers of the order of 10-2 cm-1. The experimental and DFT studies evidence a correlation between J values and porphyrin plane tilting angle and distortion. Pulsed EPR analysis shows that the two vanadyl dimers maintain the coherence time of the monomer. With the obtained spin Hamiltonian parameters, we identify suitable transitions that could be used as computational basis states. Our results, coupled with the evaporability of porphyrin systems, establish this class of dimers as extremely promising for quantum information processing applications.

Correction: An exchange coupled meso-meso linked vanadyl porphyrin dimer for quantum information processing.

[This corrects the article DOI: 10.1039/D2SC04969D.].

Drug Checking as Strategy for Harm Reduction in Recreational Contests: Evaluation of Two Different Drug Analysis Methodologies.

Introduction: Drug checking as a part of drug harm-reduction strategies represents an essential aspect of public health policies. It focuses on rapid identification of drugs that individuals intend to use during night events, in order to implement health-protective behaviors. Chemical drug analysis techniques vary considerably, from simple colorimetric reagents to advanced forensic methods such as gas chromatography/mass spectrometry (GC/MS). Materials and Methods: In 2019, drug-check services were offered at some night events in Umbria (Central Italy). One hundred and twenty attendees directly delivered unidentified substances to a harm-reduction worker, who collected a few milligrams of the substances on ceramic plates and added a drop of colorimetric reagent. Multiple reagents were used to increase the diagnostic capacity of a substance, which may react with a specific drug or a few drugs. Later, a fraction of the samples was analyzed by GC/MS. The concordance of the results obtained using these two methodologies and the intended behaviors of consumers after being informed of the test result was evaluated. Results: We analyzed 120 samples by colorimetric test: 32 MDMA, 25 ketamine, 10 amphetamine, 11 cocaine, 8 heroin, and 4 LSD samples. The results were inconclusive for 29 samples. The GS/MS analysis confirmed MDMA in 84%, ketamine in 78%, amphetamine in 91%, cocaine in 92%, heroin in 88%, and LSD in 100% of the samples. The results of samples with inconclusive results were as follows: 2, MDMA; 7, ketamine; 2, amphetamine; 2, cocaine; 2, heroin; 2, mephedrone; 6, mixes; 1, debris; and 5, adulterants as the main component. Twenty-one of 29 participants reported that they had no intention of consuming the unidentified substance. Discussion: The high percentage of individuals who claimed no intention of consuming the unidentified drugs indicates that drug checking is viable as a part of drug harm-reduction strategies. Overall, colorimetric reagents showed a good performance with regard to samples being unadulterated (LSD) or minimal in quantity, but failed to identify mixtures of substances and the adulterants present in them. Therefore, the use of more discriminatory on-site methods such as Raman or infrared spectrometry is strongly recommended.

Temperature Dependence of Spin-Phonon Coupling in [VO(acac)2]: A Computational and Spectroscopic Study.

Molecular electronic spins are good candidates as qubits since they are characterized by a large tunability of their electronic and magnetic properties through a rational chemical design. Coordination compounds of light transition metals are promising systems for spin-based quantum information technologies, thanks to their long spin coherence times up to room temperature. Our work aims at presenting an in-depth study on how the spin-phonon coupling in vanadyl-acetylacetonate, [VO(acac)2], can change as a function of temperature using terahertz time-domain spectroscopy and density functional theory (DFT) calculations. Powder THz spectra were recorded between 10 and 300 K. The temperature dependence of vibrational frequencies was then accounted for in the periodic DFT calculations using unit-cell parameters measured at two different temperatures and the optimized ones, as usually reported in the literature. In this way, it was possible to calculate the observed THz anharmonic frequency shift with high accuracy. The overall differences in the spin-phonon coupling magnitudes as a function of temperature were also highlighted showing that the computed trends have to be ascribed to the anisotropic variation of cell parameters.

La Asociación Argentina de Terapistas Ocupacionales sesenta años después de su creación. El mismo espíritu ante nuevos desafíos / The Argentine Association of Occupational Therapists sixty years after its creation. Same spirit in the face of new challenges / A Associação Argentina de Terapeutas Ocupacionais sessenta anos após sua criação. O mesmo espírito diante de novos desafios

El artículo presenta los inicios en la fundación de la Asociación Argentina de Terapistas Ocupacionales, su desarrollo, acciones realizadas y la conformación actual. Asimismo, da cuenta de la organización profesional en el territorio nacional argentino a partir de la creación de dicha Asociación, en 1962, hasta la conformación de la Red Nacional de Terapia Ocupacional en el año 2016. Se menciona cómo se organiza el sistema de salud en Argentina, para comprender sus particularidades al momento de constituirse las organizaciones de profesionales. También expone las articulaciones de la Asociación con otros actores y organismos públicos en las acciones que lleva adelante. Se enuncian algunas de las gestiones desarrolladas por la Asociación, así como otras realizadas de forma colectiva con las organizaciones profesionales que conforman la Red Nacional de Terapia Ocupacional.

This article presents the beginnings of the Argentine Association of Occupational Therapists foundation, its development, actions carried out, and the current conformation. Likewise, it accounts for the professional organization throughout the national territory from the Association's inception in 1962 until the formation of the National Network of Occupational Therapy in 2016. It mentions how the health system in Argentina is organized to understand its particularities at the time of constituting professional organizations and the articulations of the Association with other actors and public organizations for action. Some of the steps developed by the Association collectively with other organizations and professional associations that make up the National Network of Occupational Therapy, are stated.

O artigo apresenta o surgimento da fundação da Associação Argentina de Terapeutas Ocupacionais, seu desenvolvimento, ações realizadas e sua atual conformação. Da mesma forma responde pela organização profissional no território nacional argentino desde a criação desta Associação, em 1962, até a formação da Rede Nacional de Terapia Ocupacional em 2016. Menciona-se como o sistema de saúde se organiza na Argentina, para entender suas particularidades no momento da constituição de organizações profissionais. Também expõe as articulações da Associação com outros atores e órgãos públicos nas ações que realiza. Alguns dos esforços desenvolvidos pela Associação são enunciados, assim como outros realizados coletivamente com as organizações profissionais que compõem a Rede Nacional de Terapia Ocupacional.

Formación y capacitación en salud mental / Education and training in mental health

Para adecuar la formación de RRHH a la Ley Nº 26.657 (LNSM), elaboraron recomendaciones señalando la necesidad de orientar integralmente contenidos de la formación de profesionales con énfasis en los ejes: enfoque de derechos, inclusión social, salud pública e interdisciplina como ejes transversales para la formación, extensión e investigación. OBJETIVO describir los obstáculos identificados en el cumplimiento de las Recomendaciones del Art. 33 de la LNSM en la formación universitaria y la capacitación en servicio de salud mental del Área Metropolitana de Buenos Aires (AMBA). Diseño exploratorio descriptivo para la caracterización de las capacitaciones en servicios y los planes de estudio vigentes (Enfermería, Medicina, Trabajo Social, Terapia Ocupacional y Psicología) de Universidades mediante observación sistemática de fuentes documentales (planes de estudio, programas, recomendaciones, lineamientos), y triangulación metodológica con programas de asignaturas y entrevistas a informantes claves. Se analizaron 39 planes, la mayoría no menciona la LNSM. Los contenidos y ejes de SM son abordados con diferente profundidad y a veces conceptualmente contradictorios con la ley. El eje de mayor cobertura es Interdisciplina incluido en todos los planes pero con diferentes abordajes. Los ejes Salud Pública e Inclusión Social tienen menos referencias. Sobre Enfoque de Derechos incluyen pocas normativas específicas. De los 293 programas de capacitación en servicio analizados los ejes con mayor cobertura son Salud Pública (46%) e Inclusión Social (24%). Sólo el 4% de los programas incluyen todos los ejes pero focalizando en algunos principios. Hay escasez de referencias explícitas a los requerimientos de la ley y presencia de contenidos, bibliografía o enfoques de difícil valoración respecto del marco normativo. Hay escasa articulación intersectorial e interjurisdiccional