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Objective: The Virtual Naval Hospital (VNH) is a digital library designed to meet the information needs of U.S. Navy medical professionals. The goal of this study was to determine whether the VNH promoted health and improved patient care in a cost-effective manner.Design and Measurements: An economic analysis determining the costs and benefits from the perspective of the U.S. Navy was conducted. As part of this analysis, medical professionals were surveyed from February to August 2000.Results: Respondents used the VNH for a variety of professional activities (average, 8.2 h/wk). Respondents (70%) thought that VNH usage improved patient care. Medical providers thought it improved their diagnosis (70%) and treatment (60%). Respondents stated that the VNH affected 81 medical evacuations and 668 sick-in-quarter days. Overall content satisfaction was 94%. The VNH had a net savings of $143,848/yr and a cost/benefit ratio of 55.9%.Conclusions: The VNH has a beneficial impact on the Navy's health care system by improving health promotion and patient care and by being economically cost-effective. [ABSTRACT FROM AUTHOR]

irect Air Capture (DAC) is an emerging form of atmospheric carbon dioxide removal. Conventional DAC sorbents utilize swings in temperature and/or pressure, which are energy intensive and hinders large-scale deployment. In this work, we demonstrate a green, aqueous electrochemical DAC system that employs Alizarin Red S (ARS) as an electroactive capturing agent. The system has an estimated minimum theoretical energy requirement of 24.6 kJe/mole of CO2, demonstrated reversible electrochemical behavior over 100 cycles and 205 hours, and maintained an average coulombic efficiency of 100% with an average capacity retention of 99.8%. With a techno-economic analysis, we highlight the impact of current density and electrode surface area on levelized costs, and we describe a path to lower the cost of DAC below US$500 per tonne of CO2., (© 2024 Wiley‐VCH GmbH.)

Background: There is a dearth of artificial intelligence (AI) development and research dedicated to pediatric radiology. The newest iterations of large language models (LLMs) like ChatGPT can process image and video input in addition to text. They are thus theoretically capable of providing impressions of input radiological images., Objective: To assess the ability of multimodal LLMs to interpret pediatric radiological images., Materials and Methods: Thirty medically significant cases were collected and submitted to GPT-4 (OpenAI, San Francisco, CA), Gemini 1.5 Pro (Google, Mountain View, CA), and Claude 3 Opus (Anthropic, San Francisco, CA) with a short history for a total of 90 images. AI responses were recorded and independently assessed for accuracy by a resident and attending physician. 95% confidence intervals were determined using the adjusted Wald method., Results: Overall, the models correctly diagnosed 27.8% (25/90) of images (95% CI=19.5-37.8%), were partially correct for 13.3% (12/90) of images (95% CI=2.7-26.4%), and were incorrect for 58.9% (53/90) of images (95% CI=48.6-68.5%)., Conclusion: Multimodal LLMs are not yet capable of interpreting pediatric radiological images., (© 2024. The Author(s), under exclusive licence to Springer-Verlag GmbH Germany, part of Springer Nature.)

The production of aluminum (Al) metal-organic frameworks (MOFs) by electrosynthesis using solid-state Al electrodes always faces significant challenges due to the formation of a passivating aluminum oxide layer in the process. Here, we developed a liquid-metal-based method to electrosynthesize an aluminum Al-MOF (MIL-53). This method uses a liquid-state gallium (Ga) anode as a reservoir and activator for a light metal, Al, in the form of Al-Ga alloys that releases Al 3+ for the electrosynthesis of Al-MOFs. Introducing Ga into the system inhibits the formation of aluminum oxide passivation layer and promotes the electrochemical reaction for Al-MOF synthesis. The electrosynthesis using liquid Al-Ga alloy is conducted at ambient temperatures for long durations without requiring pretreatment for aluminum oxide removal. We show that the Al-MOF products synthesized from 0.40 wt % Al in liquid Ga lead to the highest crystallinity and possess a specific surface area greater than 800 m 2 g -1 and a low capacity for CO 2 adsorption that can be used as a potential matrix for CO 2 /N 2 separation. This work provides evidence that employing liquid-metal electrodes offers a viable pathway to circumvent surface passivation effects that inevitably occur when using conventional solid metals. It also introduces an efficient electrosynthesis method based on liquid metals for producing atomically porous materials.

The hybrid ultraporous material TIFSIX-Ni ([Ni(pyrazine) 2 (TiF 6 )] n ) was incorporated into a composite ink for the first time for the three-dimensional (3D) printing of monoliths. The large-scale synthesis of TIFSIX-Ni was completed using two different Ni(II) salts, with CO 2 uptakes of 1.90 mmol g -1 achieved using mechanochemically assisted thermal synthesis. The monoliths were then tested for the capture and release of CO 2 gas using electric swing adsorption (ESA) under dry and humid conditions. A working capacity of 1.7% was achieved (comparing dynamic data with isotherm data) when a current of 2.1 A was applied for 10 min. The monolith could be cycled repeatedly for 6 h without impacting the performance of the material or loss of capacity. Part of this work explored the improvement of mechanochemically assisted synthetic methods of TIFISX-Ni in reducing the costs associated with large-scale production, allowing for improvements in the overall scale-up and processability of the material for industrial applications.

Recently, there has been significant interest in the use of chiral metal-organic frameworks (MOFs) and coordination polymers (CPs) for photonics applications. The promise of these materials lies in the ability to tune their properties through judicious selection of the metal and ligand components. Additionally, the interaction of guest species with the host framework can be exploited to realise new functionalities. In this review, we outline the methods for synthesising chiral MOFs and CPs, then analyse the recent innovations in their use for various optical and photonics applications. We focus on two emerging directions in the field of MOF chemistry - circularly polarised luminescence (CPL) and chiroptical switching - as well as the latest developments in the use of these materials for second-order nonlinear optics (NLO), particularly second-harmonic generation (SHG). The current challenges encountered so far, their possible solutions, and key directions for further research are also outlined. Overall, given the results demonstrated to date, chiral MOFs and CPs show great promise for use in future technologies such as optical communication and computing, optical displays, and all-optical devices.

Molecular electronic spin qubits are promising candidates for quantum information science applications because they can be reliably produced and engineered via chemical design. Embedding electronic spin qubits within two-dimensional polymers (2DPs) offers the possibility to systematically engineer inter-qubit interactions while maintaining long coherence times, both of which are prerequisites to their technological utility. Here, we introduce electronic spin qubits into a diamagnetic 2DP by n -doping naphthalene diimide subunits with varying amounts of CoCp 2 and analyze their spin densities by quantitative electronic paramagnetic resonance spectroscopy. Low spin densities ( e.g. , 6.0 × 10 12 spins mm -3 ) enable lengthy spin-lattice ( T 1 ) and spin-spin relaxation ( T 2 ) times across a range of temperatures, ranging from T 1 values of 164 ms at 10 K to 30.2 μs at 296 K and T 2 values of 2.36 μs at 10 K to 0.49 μs at 296 K for the lowest spin density sample examined. Higher spin densities and temperatures were both found to diminish T 1 times, which we attribute to detrimental cross-relaxation from spin-spin dipolar interactions and spin-phonon coupling, respectively. Higher spin densities decreased T 2 times and modulated the T 2 temperature dependence. We attribute these differences to the competition between hyperfine and dipolar interactions for electron spin decoherence, with the dominant interaction transitioning from the former to the latter as spin density and temperature increase. Overall, this investigation demonstrates that dispersing electronic spin qubits within layered 2DPs enables chemical control of their inter-qubit interactions and spin decoherence times.

Objective: Educator roles in medicine are expanding yet career paths and definitions of successful careers are not uniformly agreed upon. Educator success from their own perspective has not been broadly explored as these studies usually occur from the institutional or organizational viewpoint. This study examined the impact of a national educational faculty development program (FDP) for academic pediatricians on educators' self-description of their own professional and personal success., Methods: This was a cross-sectional, qualitative study of FDP alumni between 2019-2021. Interviews explored participants perspectives on their professional success, and supports and barriers. Using an iterative process, thematic analysis of the data identified 6 themes., Results: Fourteen scholars were interviewed. All felt they were successful citing both outcome and impact measures categorized into 6 themes: personal attributes, adequate resources and barriers, foundational skill development, experiencing strong mentoring and networking, engaging, and being connected to a community of practice and self-identifying as a medical educator. To view the data holistically, a model incorporating 3 frameworks was developed., Conclusions: These educators viewed themselves as successful academic educators. While papers, promotions and positions were important, educators viewed impact in mentoring and collaborations with others, along with acquired expertise and an expanded viewpoint of the field and themselves as equally important. Educators and leaders could use these elements for their own self-assessment and support, FDP development and enhancement, and for investment in programs and faculty educators., (Copyright © 2022 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.)

A 3D Hofmann-like metal-organic framework has been prepared which contains a 2,1,3-benzothiadiazole-based pillaring ligand. Encapsulation of a polycyclic aromatic hydrocarbon, chrysene, within the pore structure leads to a new pathway to multi-step spin crossover behaviour in which the observed two-step spin transition arises due to the presence of multiple site environments associated with local guest positional effects within the host lattice.

The two-dimensional (2-D) framework, [Cu(BTDAT)(MeOH)] {BTDAT = bis-[1,2,5]-thiadiazolo-tetracyanoquinodimethane}, possesses remarkable multi-step redox properties, with electrochemical studies revealing six quasi-stable redox states in the solid state. In situ electron paramagnetic resonance and visible-near infrared spectroelectrochemistry elucidated the mechanism for these multi-step redox processes, as well as the optical and electrochromic behavior of the BTDAT ligand and framework. In studying the structural, spectroscopic, and electronic properties of [Cu(BTDAT)(MeOH)], the as-synthesized framework was found to exist in a mixed-valence state with thermally-activated semiconducting behavior. In addition to pressed pellet conductivity measurements, single-crystal conductivity measurements using a pre-patterned polydimethylsiloxane layer on a silicon substrate provide important insights into the anisotropic conduction pathways. As an avenue to further understand the electronic state of [Cu(BTDAT)(MeOH)], computational band structure calculations predicted delocalized electronic transport in the framework. On the balance of probabilities, we propose that [Cu(BTDAT)(MeOH)] is a Mott insulator (i.e., electron correlations cause a metal-insulator transition). This implies that the conductivity is incoherent. However, we are unable to distinguish between activated transport due to Coulombically bound electron-hole pairs and a hopping mechanism. The combined electrochemical, electronic, and optical properties of [Cu(BTDAT)(MeOH)] shine a new light on the experimental and theoretical challenges for electroactive framework materials, which are implicated as the basis of advanced optoelectronic and electrochromic devices.

Porosity and surface area analysis play a prominent role in modern materials science. At the heart of this sits the Brunauer-Emmett-Teller (BET) theory, which has been a remarkably successful contribution to the field of materials science. The BET method was developed in the 1930s for open surfaces but is now the most widely used metric for the estimation of surface areas of micro- and mesoporous materials. Despite its widespread use, the calculation of BET surface areas causes a spread in reported areas, resulting in reproducibility problems in both academia and industry. To prove this, for this analysis, 18 already-measured raw adsorption isotherms were provided to sixty-one labs, who were asked to calculate the corresponding BET areas. This round-robin exercise resulted in a wide range of values. Here, the reproducibility of BET area determination from identical isotherms is demonstrated to be a largely ignored issue, raising critical concerns over the reliability of reported BET areas. To solve this major issue, a new computational approach to accurately and systematically determine the BET area of nanoporous materials is developed. The software, called "BET surface identification" (BETSI), expands on the well-known Rouquerol criteria and makes an unambiguous BET area assignment possible., (© 2022 The Authors. Advanced Materials published by Wiley-VCH GmbH.)

Pediatric medical educators, with their multitude of responsibilities, may have difficulty staying abreast with both medical education and specialty specific medical literature. The body of medical literature is growing at an exponential rate. This annotated bibliography serves as a summary of highlighted medical education literature in the year 2020. The purpose was to identify manuscripts which have the potential to significantly influence a pediatric medical educator's practice. The authors reviewed abstracts from 14 medical education and specialty journals using a two-staged review process. Each stage of review was completed by 2 different authors. A total of 1861 abstracts were reviewed and ultimately 15 key manuscripts were identified. The authors grouped the manuscripts into 6 core domains: diversity and inclusion, faculty development, feedback, learner development, mentorship, and teaching skills. Condensed summaries of each medical education manuscript likely to influence educational practice are provided by the authors in this annotated bibliography., (Copyright © 2021 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.)

Electroactive metal-organic frameworks (MOFs) are an attractive class of materials owing to their multifunctional 3-dimensional structures, the properties of which can be modulated by changing the redox states of the components. In order to realise both fundamental and applied goals for these materials, a deeper understanding of the structure-function relationships that govern the charge transfer mechanisms is required. Chemical or electrochemical reduction of the framework [Zn(BPPFTzTz)(tdc)]·2DMF, hereafter denoted ZnFTzTz (where BPPFTzTz = 2,5-bis(3-fluoro-4-(pyridin-4-yl)phenyl)thiazolo[5,4- d ]thiazole), generates mixed-valence states with optical signatures indicative of through-space intervalence charge transfer (IVCT) between the cofacially stacked ligands. Fluorination of the TzTz ligands influences the IVCT band parameters relative to the unsubstituted parent system, as revealed through Marcus-Hush theory analysis and single crystal UV-Vis spectroscopy. Using a combined experimental, theoretical and density functional theory (DFT) analysis, important insights into the effects of structural modifications, such as ligand substitution, on the degree of electronic coupling and rate of electron transfer have been obtained.

A new metal-organic framework (MOF) containing a Mn(II) salen complex (BET surface area = 967 ± 6 m 2 g -1 ) undergoes a reversible crystalline-to-amorphous transformation. Experimental studies and computational calculations show that the MOF is stable to a one-electron reduction at more anodic potentials than the corresponding discrete complex.

A remarkably flexible, multifunctional, 2D coordination polymer exhibiting an unprecedented mode of reversible mechanical motion, enabling pores to open and close, is reported. Such multifunctional materials are highly sought after, owing to the potential to exploit coexisting electronic and mechanical functionalities that underpin useful technological applications such as actuators and ultrasensitive detectors. The coordination polymer, of composition Mn(F 4 TCNQ)(py) 2 (F 4 TCNQ = 2,3,5,6-tetrafluoro-7,7,8,8-tetracycanoquinodimethane; py = pyridine), consists of Mn(II) centers bridged by F 4 TCNQ dianions and coordinated by py molecules that extend above and below the 2D network. Exposure of Mn(F 4 TCNQ)(py) 2 , in its collapsed state, to carbon dioxide results in a pore-opening process at a threshold pressure for a given temperature. In addition to carbon dioxide, a variety of volatile guests may be incorporated into the pores, which are lined with electron-rich F 4 TCNQ dianions. The inclusion of electron-deficient guests such as 1,4-benzoquinone, nitrobenzene, maleic anhydride, and iodine into the pores is accompanied by a striking color change associated with a new host-guest charge-transfer interaction and an improvement in the semiconductor behavior, with the iodine adduct showing an increase in conductivity of almost 5 orders of magnitude. Experimental and density functional theory calculations on this remarkable multifunctional material demonstrate a reduction in the optical band gap with increasing electron affinity of the guest.

The incorporation of photoactive donor-acceptor Stenhouse adduct (DASA) moieties into Metal-Organic Frameworks (MOFs) provides a new route to the development of visible light switching materials. Herein, a DUT-5 mixed-linker defect series was exploited to produce a derivative group of DASA-modified materials via postsynthetic modification (PSM). The photoactive MOFs exhibited conversion stimulated by visible wavelengths and were stable following multiple cycles. Thermodynamic and metastable states persisted over an extended time period.

Pediatric medical educators have the dual challenge of remaining up-to-date in the field of pediatrics and in the field of medical education. Due to the volume of information published in these 2 fields it can be nearly impossible to remain current in both fields of practice. To facilitate interpretation of the most recent medical education research, the authors conducted an annotated bibliography of medical education literature published in 2019. The purpose of this annotated bibliography was to identify manuscripts which had the potential to significantly influence a pediatric educator's practice. Using a 2-staged review process, the authors reviewed abstracts from 13 medical education and specialty journals. All reviews were independently completed by 2 different reviewers for each journal in both stages. A total of 4700 abstracts were reviewed and 17 key manuscripts were identified. The authors grouped the key manuscripts into 6 core themes: bedside teaching, learning climate, bias, learner autonomy, learner in trouble, and resident competency. This annotated bibliography provides the authors' condensed summary of the medical education manuscripts most likely to influence educational practices for the busy pediatric medical educator., (Copyright © 2021 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.)

A series of stable radical 2D metal-organic frameworks has been assembled. (m-TTFTB) 3 (m-Tetrathiafulvalene-tetrabenzoate) trimer building blocks are beneficial for the stability of the radicals due to delocalization of the unpaired electron. Hexanuclear rare-earth-cluster-based 1D chains further enhance the stability of the frameworks. The radical state of the middle TTF in the trimer has been observed by the change of central C-C and C-S bond distances and the configuration of the TTF by single-crystal X-ray diffraction. The radical characteristics are also confirmed by electron paramagnetic resonance, UV/Vis-NIR absorption, and X-ray photoelectron spectroscopy experiments. Stability tests showed that the radicals are stable even in solutions and under acid/base environments (pH 1-12). Owing to efficient light absorption due to intramolecular charge transfer, low thermal conductivity, and outstanding stability, the radical 2D Dy-MOF shows excellent photothermal properties, an increase of 34.7 °C within 240 s under one-sun illumination., (© 2020 Wiley-VCH GmbH.)

Using the redox-active tetrathiafulvalene tetrabenzoate (TTFTB 4- ) as the linker, a series of stable and porous rare-earth metal-organic frameworks (RE-MOFs), [RE 9 (μ 3 -OH) 13 (μ 3 -O)(H 2 O) 9 (TTFTB) 3 ] (1-RE, where RE=Y, Sm, Gd, Tb, Dy, Ho, and Er) were constructed. The RE 9 (μ 3 -OH) 13 (μ 3 -O) (H 2 O) 9 ](CO 2 ) 12 clusters within 1-RE act as segregated single-molecule magnets (SMMs) displaying slow relaxation. Interestingly, upon oxidation by I 2 , the S=0 TTFTB 4- linkers of 1-RE were converted into S= 1 / 2 TTFTB .3- radical linkers which introduced exchange-coupling between SMMs and modulated the relaxation. Furthermore, the SMM property can be restored by reduction in N,N-dimethylformamide. These results highlight the advantage of MOFs in the construction of redox-switchable SMMs., (© 2020 Wiley-VCH GmbH.)

Innovative and robust photosensitisation materials play a cardinal role in advancing the combined effort towards efficient solar energy harvesting. Here, we demonstrate the photocathode functionality of a Metal-Organic Framework (MOF) featuring cofacial pairs of photo- and electro-active 1,4,5,8-naphthalenediimide (NDI) ligands, which was successfully applied to markedly reduce the overpotential required for CO 2 reduction to CO by a well-known rhenium molecular electrocatalyst. Reduction of [Cd(DPNDI)(TDC)] n (DPNDI = N , N '-di(4-pyridyl)-1,4,5,8-naphthalenediimide, H 2 TDC = thiophene-2,5-dicarboxylic acid) to its mixed-valence state induces through-space Intervalence Charge Transfer (IVCT) within cofacial DPNDI units. Irradiation of the mixed-valence MOF in the visible region generates a DPNDI photoexcited radical monoanion state, which is stabilised as a persistent species by the inherent IVCT interactions and has been rationalised using Density Functional Theory (DFT). This photoexcited radical monoanion state was able to undergo charge transfer (CT) reduction of the rhenium molecular electrocatalyst to effect CO generation at a lower overpotential than that required by the discrete electrocatalyst itself. The exploitation of cofacial MOFs opens new directions for the design philosophy behind light harvesting materials., Competing Interests: The authors declare no conflict of interest., (This journal is © The Royal Society of Chemistry.)

Functionalizing the redox-active tetrathiafulvalene (TTF) core with groups capable of coordination to metals provides new perspectives on the modulation of architectures and electronic properties of organic-inorganic hybrid materials. With a view to extending this concept, we have now synthesized nickel bis(dithiolene-dibenzoic acid), [Ni(C 2 S 2 (C 6 H 4 COOH) 2 ) 2 ], which can be considered as the inorganic analogue of the organic tetrathiafulvalene-tetrabenzoic acid (H 4 TTFTB). Likewise, [Ni(C 2 S 2 (C 6 H 4 COOH) 2 ) 2 ] is a redox-active linker for new functional metal-organic frameworks, as demonstrated here with the synthesis of [Mn 2 {Ni(C 2 S 2 (C 6 H 4 COO) 2 ) 2 }(H 2 O) 2 ]·2DMF, ( 1 , DMF = N,N -dimethylformamide). 1 is isomorphic to the reported [Mn 2 (TTFTB)(H 2 O) 2 ] ( 2 ) but is a better electrochemical glucose sensor due to the multiple oxidation-reduction states of the [NiS 4 ] core, which allow glucose to be oxidized to glucolactone by the high oxidation state [NiS 4 ] center. As a non-enzymatic glucose sensor, 1 on Cu foam ( CF ), 1-CF , was synthesized by a one-step hydrothermal method and exhibited an excellent electrochemical performance. The fabricated 1-CF electrode offers a high sensitivity of 27.9 A M -1 cm -2 , with a wide linear detection range from 2.0 × 10 -6 to 2.0 × 10 -3 M, a low detection limit of 1.0 × 10 -7 M (signal/noise = 3), and satisfactory stability and reproducibility.

A one-dimensional Fe II coordination polymer (CP) has been formed which includes the redox-active ligand bis-pyridyltetrathiafulvalene (py 2 TTF) and a Schiff base-like N 2 O 2 ligand. This CP is both spin crossover (SCO) and redox-active in the solid-state, and chemical oxidation results in SCO modification.

Pediatric educators desire to and should strive to incorporate current educational methods and ideas into their professional practices. The overwhelming volume of medical education literature makes this difficult. This article provides an overview of 18 key articles from the 2018 literature that the authors considered impactful for the field of pediatric medical education. The author group has extensive combined leadership experience and expertise across the continuum of pediatric medical education and used an iterative, staged process to review 2270 abstracts from 13 medical education-related journals. This process aimed to identify a subset of articles that were most relevant to educational practice and scholarship and most applicable to pediatric medical education. Author pairs independently reviewed and scored abstracts and reached consensus to identify the abstracts that best met these criteria. Selected abstracts were discussed using different author pairs to determine the final articles included in this review. The 18 articles selected are summarized. The results showed a cluster of studies related to assessment, learner education and teaching, communication, and culture and climate. This review offers a summary for educators interested in remaining knowledgeable and current regarding the most relevant and valuable information in the field of medical education., (Copyright © 2020 Academic Pediatric Association. Published by Elsevier Inc. All rights reserved.)

Reversible structural transformations of porous coordination frameworks in response to external stimuli such as light, electrical potential, guest inclusion or pressure, amongst others, have been the subject of intense interest for applications in sensing, switching and molecular separations. Here we report a coordination framework based on an electroactive tetrathiafulvalene exhibiting a reversible single crystal-to-single crystal double [2 + 2] photocyclisation, leading to profound differences in the electrochemical, optical and mechanical properties of the material upon light irradiation. Electrochemical and in situ spectroelectrochemical measurements, in combination with in situ light-irradiated Raman spectroscopy and atomic force microscopy, revealed the variable mechanical properties of the framework that were supported using Density Functional Theory calculations. The reversible structural transformation points towards a plethora of potential applications for coordination frameworks in photo-mechanical and photoelectrochemical devices, such as light-driven actuators and photo-valves for targeted drug delivery.

In designing multifunctional materials for potential switches that can be used as memory devices, the high-spin (HS) to low-spin (LS) crossover (SCO) one-dimensional polymer, [Fe II (L)(4,4'-bpy)] n , was constructed from a designed redox-active tetrathiafulvalene (TTF) functionalized Schiff-base and the ditopic linker 4,4'-bipyridine (bpy). It exhibits an 8 K hysteretic SCO centred at T 1/2 = 325 K which is coupled to changes in its dielectric constant. The crystal structures above and below the transition temperature reveal similar parallel linear ···Fe-bpy-Fe-bpy··· chains displaying expansion of the Fe II octahedron in the HS state. Density functional theory (DFT) calculations reveal a concerted electronic charge and spin change represented by the Mülliken charge of the Fe and the magnitude and direction of the dipole moment which substantiate the experimental observations., (This journal is © The Royal Society of Chemistry 2020.)

Gaining a fundamental understanding of charge transfer mechanisms in three-dimensional Metal-Organic Frameworks (MOFs) is crucial to the development of electroactive and conductive porous materials. These materials have potential in applications in porous conductors, electrocatalysts and energy storage devices; however the structure-property relationships pertaining to charge transfer and its quantification are relatively poorly understood. Here, the cofacial Cd(ii)-based MOF [Cd(BPPTzTz)(tdc)]·2DMF (where BPPTzTz = 2,5-bis(4-(pyridin-4-yl)phenyl)thiazolo[5,4- d ]thiazole, tdc 2- = 2,5-thiophene dicarboxylate) exhibits Intervalence Charge Transfer (IVCT) within its three-dimensional structure by virtue of the close, cofacial stacking of its redox-active BPPTzTz ligands. The mixed-valence and IVCT properties are characterised using a combined electrochemical, spectroelectrochemical and computational approach. Single crystal electronic absorption spectroscopy was employed to obtain the solid-state extinction coefficient, enabling the application of Marcus-Hush theory. The electronic coupling constant, H ab , of 145 cm -1 was consistent with the localised mixed-valence properties of both this framework and analogous systems that use alternative methods to obtain the H ab parameter. This work demonstrates the first report of the successful characterisation of IVCT in a MOF material using single crystal electronic absorption spectroscopy and serves as an attractive alternative to more complex methods due to its simplicity and applicability., Competing Interests: There are no conflicts to declare., (This journal is © The Royal Society of Chemistry.)

A 2-D coordination framework, (NEt 4 ) 2 [Fe 2 (fan) 3 ] ( 1·5(acetone) ; H 2 fan = 3,6-difluoro-2,5-dihydroxy-1,4-benzoquinone), was synthesized and structurally characterized. The compound is structurally analogous to a formerly elucidated framework, (NEt 4 ) 2 [Fe 2 (can) 3 ] (H 2 can = 3,6-dichloro-2,5-dihydroxy-1,4-benzoquinone), and adopts a 2-D (6,3) topology with the symmetrical stacking of [Fe 2 (fan) 3 ] 2- sheets that are held in position by the NEt 4 + cations between the sheets. The investigation of the dc and ac magnetic properties of 1·5(acetone) revealed ferromagnetic ordering behavior and slow magnetization relaxation, as evinced from ac susceptibility measurements. Furthermore, the exposure of 1·5(acetone) to air led to the formation of a heptahydrate 1·7H 2 O which displayed distinct magnetic properties. The study of the redox state and extent of delocalization in 1·5(acetone) was undertaken via crystallography, in combination with Mössbauer and vis-NIR spectroscopy, to reveal the mixed-valence and delocalized nature of the as-synthesized material. As a result, the conductivity studies conducted on a pressed pellet showed a relatively high conductivity of 1.8 × 10 -2 S cm -1 (300 K). In order to compare structurally related anilate-based structures, a relationship among the redox state, spectroscopic properties, and electronic properties was elucidated in this work. A preliminary investigation of 1·5(acetone) as a candidate anode material in lithium ion batteries revealed a high reversible capacity of 676.6 mAh g -1 and high capacity retention.

Rigid dinuclear ruthenium complexes containing non-aromatic caged and polycyclic spacer groups were synthesised and characterised. The complexes, [trans,trans-{Ru(dmpe)2(C[triple bond, length as m-dash]CtBu)}2(μ-C[triple bond, length as m-dash]C-X-C[triple bond, length as m-dash]C)], where X = 1,4-bicyclo[2.2.2]octane (C8H12) or 1,12-p-carborane (p-C2B10H10), were formed via the metathesis of terminal organic bisacetylenes with the methylruthenium complex, [trans-Ru(dmpe)2(CH3)(C[triple bond, length as m-dash]CtBu)], under mild conditions. Electrochemical studies demonstrated electronic interactions across the non-aromatic caged and polycyclic spacers was less than in the analogous complex with an aromatic spacer group, [trans,trans-{Ru(dmpe)2(C[triple bond, length as m-dash]CtBu)}2(μ-C[triple bond, length as m-dash]C-p-C6H4-C[triple bond, length as m-dash]C)]. Mononuclear complexes, [trans-Ru(dmpe)2(C[triple bond, length as m-dash]CtBu)(C[triple bond, length as m-dash]C-X-C[triple bond, length as m-dash]CH)], were also synthesised. [trans-Ru(dmpe)2(C[triple bond, length as m-dash]CtBu)(C[triple bond, length as m-dash]C-C8H12-C[triple bond, length as m-dash]CH)] and [trans,trans-{Ru(dmpe)2(C[triple bond, length as m-dash]CtBu)}2(μ-C[triple bond, length as m-dash]C-p-C2B10H10-C[triple bond, length as m-dash]C)] were structurally characterised by X-ray crystallography.

Electroactive and conducting framework materials, encompassing coordination polymers and metal-organic frameworks, have captured the imagination of the scientific community owing to their highly designable nanoporous structures and their potential applications in electrochromic devices, electrocatalysts, porous conductors, batteries and solar energy harvesting systems, among many others. While they are now considered integral members of the broader field of inorganic materials, it is timely to reflect upon their strengths and challenges compared with 'traditional' solid-state materials such as minerals, pigments and zeolites. Indeed, the latter have been known since ancient times and have been prized for centuries in fields as diverse as art, archaeology and industrial catalysis. This opinion piece considers a brief historical perspective of traditional electroactive and conducting inorganic materials, with a view towards very recent experimental progress and new directions for future progress in the burgeoning area of coordination polymers and metal-organic frameworks. Overall, this article bears testament to the rich history of electroactive solids and looks at the challenges inspiring a new generation of scientists. This article is part of the theme issue 'Mineralomimesis: natural and synthetic frameworks in science and technology'.

In search of multifunctional metal-organic frameworks (MOFs), redox-active donors and acceptors, namely, tetrathiafulvalene (TTF) and 7,7,8,8-tetracyanoquinodimethane (TCNQ), were concomitantly used as skeletal components with diamagnetic metal nodes (Cd and Zn) to construct unique framework materials. Six isostructural frameworks were synthesized by diffusion of metal salts, TTF(py) 4 , and either paramagnetic Li(TCNQ) or diamagnetic H 2 TCNQ. They were characterized by single-crystal X-ray diffraction and FT-IR and UV-vis-NIR spectroscopy, and their physical properties were studied, including two postsynthetic modifications involving crystal-to-crystal transformations following a solid-solution reaction with I 2 . The highly colored crystals of two isostructural Zn and Cd frameworks contain undulating Cd-TTF(py) 4 layers entwined with TCNQ in a chicken-wire net as part of the skeleton of the MOF as well as TCNQ intercalated within the channels, while nitrate anions are occluded within the cavities formed by the pyridine moieties. Reaction with I 2 replaces each intercalated TCNQ •- within the channels with I 3 - . The optical properties and the electron paramagnetic resonance (EPR) spectra indicate the presence of only radical TCNQ •- in the parent compounds, while the magnetic susceptibilities enabled an estimation of the amount of TCNQ •- ( S = 1/2) leading to almost paramagnetic behavior. Solid-state electrochemistry provides evidence of several one-electron redox states corresponding to the electroactive cores.

Two tetrapyridyl ligands of 1,2,4,5-tetraethynyl(4-pyridyl)benzene (tpeb) and tetra(4-pyridyl)-tetrathiafulvalene (TTF(py) 4 ) were used to react with trinuclear (Re(CO) 4 ) 3 (C 3 N 3 S 3 ) (C 3 N 3 S 3 = cyanurate trianion) moieties to afford hexanuclear [(Re(CO) 3 ) 6 (tpeb) 2 (C 3 N 3 S 3 ) 2 ]·4CH 3 CN·toluene (1) and dodecanuclear [(Re(CO) 3 ) 12 (TTF(py) 4 ) 3 (C 3 N 3 S 3 ) 4 ]·8CH 3 CN·12DMF (2) boxes, respectively, under solvothermal conditions. Surprisingly, similar tetrapyridyl ligands with different core units (i.e., benzene and tetrathiafulvalene moieties) led to dramatically different structural motifs (i.e., hexanuclear and dodecanuclear boxes). Complex 1 forms a slightly bent trigonal-prismatic structure, containing two μ 3 -tpeb ligands and two Re 3 C 3 N 3 S 3 moieties as well as a ππ interaction distance of 3.86 Å. It is noted that complex 2 features a novel four-star structure, and three crossed tetrathiafulvalene moieties from three μ 4 -TTF(py) 4 ligands to form a triple-decker arrangement with a ππ interaction distance of 3.70 Å. Moreover, 1 and 2 display luminescence properties in the solid state along with electrochemical properties for complex 2 arising from the electroactive TTF core.

The first porous molecular conductor (PMC), which exhibits porosity, a through-space conduction pathway and rich charge carriers (electrons), was prepared through electrocrystallization from Cd 2+ and N, N'-di(4-pyridyl)-1,4,5,8-naphthalenetetracarboxdiimide (NDI-py). [Cd(NDI-py)(OH 2 ) 4 ](NO 3 ) 1.3±0.1 · nDMA (PMC-1) was assembled by π-π stacking among one-dimensional (1D) linear coordination polymers. The NDI cores were partially reduced into radical anions to form conductive π-stacked columns, yielding (1.0-3.3) × 10 -3 S cm -1 at room temperature. Moreover, the electrical conductivity was significantly enhanced by removing the solvent molecules from PMC-1, indicating that PMCs are promising as molecule-responsive conductive materials.

Metal-organic frameworks (MOFs) incorporating lanthanide nodes and tetrathiafulvalene (TTF) linkers offer a viable approach for combining redox activity and magnetism in one material. Four rare-earth lanthanide ions (RE = Tb, Dy, Ho, and Er) were found to form isostructural MOFs consisting of metal chains bridged by redox-active tetrathiafulvalene-tetrabenzoate (TTFTB 4- ) whereby the carboxylate moieties act in both anti- anti and syn- syn coordination modes. These materials display tunable redox-active properties and slow magnetic relaxation phenomenon (Er and Dy). While the as-synthesized crystals contain the neutral diamagnetic TTF moiety, using either a solid-solution electrochemical method or iodine oxidation transforms part of the latter to the paramagnetic TTF •+ radical in a single-crystal-to-single-crystal manner without altering the internal structure of the building chains and the frameworks. This is accompanied by inclusion of I 3 - replacing some of the solvents, as well as changes in the central C-C bond length of TTFTB, a strong EPR response at g ∼ 2, and an enhancement of the reflectance at low energies originating from absorption by the radical.