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BACKGROUND: Clinicians and researchers should consider the expected benefits and potential harms of an intervention. Parenting programmes are a widely used evidence-based intervention for child behaviour problems. However, few data are available on potential negative effects. The aims of this paper were to increase systematic knowledge of adverse event (AE) assessment in parenting programmes and to provide an AE assessment tool. METHODS: As part of the RISE project (prevention of child mental health problems in South-eastern Europe-adapt, optimise, test and extend parenting for lifelong health), we developed and tested an AE assessment procedure in three sequential studies for parents of children with child behaviour problems aged 2 to 9 years in North Macedonia, Republic of Moldova, and Romania. This paper reports on the development of the assessment tool in phase 1 (N = 140), phase 2 (N = 835), and the final experiences with using the optimised procedures in phase 3 (multisite randomised controlled trial, N = 823) in which AEs were assessed before, three times during intervention delivery, and at 1 year follow-up. At each time point, the participants completed a 12-item AE checklist. If moderate-to-severe problems of parent or child were reported, a structured follow-up interview was conducted. RESULTS: The response rate on the AE assessment tool increased from 6% (phase 1) to 100% (phase 3) indicating improvement in collecting these data based on the experiences of each phase. Results of the RCT (phase 3) showed generally low (S)AE frequencies with the finally optimised procedure: During the intervention, no serious adverse events (SAE) were registered; at least one AE was reported by 10% (after the first session), 7% (after the third session), and 4% (after the last fifth session) of participants. None of the identified (S)AEs was causally related to the study or intervention. Cost-benefit considerations are needed to determine the best way to ensure participant safety in parenting programmes. CONCLUSION: The applied active AE assessment procedure provides a comprehensive AE assessment tool that can be used by others-with adaptations for the specific context, if needed. Based on our experiences, we outline recommendations for future studies. TRIAL REGISTRATION: ClinicalTrials.gov, registration number phase 1: NCT03552250; phase 2: NCT03865485, phase 3: NCT04721730 . Registered on 13 January 2021.
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Comportamento Infantil , Poder Familiar , Humanos , Pré-Escolar , Criança , Feminino , Masculino , Transtornos do Comportamento Infantil/diagnóstico , Pais/psicologia , Pais/educação , Fatores de Tempo , Resultado do Tratamento , Lista de Checagem , Romênia , Medição de Risco , Moldávia , Relações Pais-FilhoRESUMO
A combined analysis of millimeter-wave (70-700 GHz) and rotationally resolved infrared (400-1200 cm-1) spectra of the ground state and seven fundamental vibrational modes of 1H-1,2,4-triazole is reported. While the lowest-energy vibrationally excited state (ν18) is well-treated using a single-state distorted-rotor Hamiltonian, the second (ν17) and third (ν16) vibrationally excited states are involved in strong c-type Coriolis coupling and require an appropriate two-state Hamiltonian. The oblate nature of 1H-1,2,4-triazole is sufficiently close to the oblate symmetric-top limit that the analysis requires the use of A-reduced, sextic centrifugally distorted-rotor Hamiltonian models in the Ir representation in order to achieve low σfit values. The coupling between ν17 (Aâ³) and ν16 (Aâ³) resulted in many transitions with slightly perturbed frequencies, many highly displaced resonant intrastate transitions, and 165 nominal interstate transitions. Modeling the spectra of ν17 and ν16 required three c-axis Coriolis-coupling terms (Fab, FabJ, and FabK) to treat the interaction. Many of the nominal interstate transitions form clearly discernible Q-branch bands, comprising degenerate sets of a- and b-type transitions. The rotational spectra of four higher-energy vibrationally excited states (ν15, ν14, ν13, and ν12), which form a complex polyad involving Coriolis and anharmonic coupling interactions, were analyzed by single-state models, thus producing only effective spectroscopic constants. Inclusion of rotationally resolved infrared transitions enabled the accurate and precise determination of vibrational band origins for the four lowest-energy fundamental states: ν18 = 542.601 824 3 (28) cm-1, ν17 = 665.183 128 5 (43) cm-1, ν16 = 682.256 910 5 (43) cm-1, and ν15 = 847.557 400 (11) cm-1.
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The rotational spectrum of 3-furonitrile has been collected from 85 to 500 GHz, spanning the most intense rotational transitions observable at room temperature. The large dipole moment imparted by the nitrile substituent confers substantial intensity to the rotational spectrum, enabling the observation of over 5600 new rotational transitions. Combined with previously published transitions, the available data set was least-squares fit to partial-octic, distorted-rotor A- and S-reduced Hamiltonian models with low statistical uncertainty (σfit < 0.031 MHz) for the ground vibrational state. Similar to its isomer 2-furonitrile, the two lowest-energy vibrationally excited states of 3-furonitrile (ν17, ν24), which correspond to the in-plane and out-of-plane nitrile bending vibrations, form an a- and b-axis Coriolis-coupled dyad. Rotationally resolved infrared transitions (30-600 cm-1) and over 4200 pure rotational transitions for both ν17 and ν24 were fit to a partial-octic, Coriolis-coupled, two-state Hamiltonian with low statistical uncertainty (σfit rot < 0.045 MHz, σfit IR < 6.1 MHz). The least-squares fitting of these vibrationally excited states provides their accurate and precise vibrational frequencies (ν17 = 168.193 164 8 (67) cm-1 and ν24 = 169.635 831 5 (77) cm-1) and seven Coriolis-coupling terms (Ga, GaJ, GaK, Fbc, FbcK, Gb, and Fac). The two fundamental states exhibit a notably small energy gap (1.442 667 (10) cm-1) and an inversion of the relative energies of ν17 and ν24 compared to those of the isomer 2-furonitrile. The rotational frequencies and spectroscopic constants of 3-furonitrile that we present herein provide a sufficient basis for conducting radioastronomical searches for this molecule across the majority of the frequency range available to current radiotelescopes.
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Parental monitoring is a construct of longstanding interest in multiple fields-but what is it? This paper makes two contributions to the ongoing debate. First, we review how the published literature has defined and operationalized parental monitoring. We show that the monitoring construct has often been defined in an indirect and nonspecific fashion and measured using instruments that vary widely in conceptual content. The result has been a disjointed empirical literature that cannot accurately be described as the unified study of a single construct nor is achieving a cumulative scientific character. Second, we offer a new formulation of the monitoring construct intended to remedy this situation. We define parental monitoring as the set of all behaviors performed by caregivers with the goal of acquiring information about the youth's activities and life. We introduce a taxonomy identifying 5 distinct types of monitoring behaviors (Types 1-5), with each behavior varying along five dimensions (performer, target, frequency, context, style). We distinguish parental monitoring from 16 other parenting constructs it is often conflated with and position monitoring as one element within the broader parent-youth monitoring process: the continuous, dyadic interplay between caregivers and youth as they navigate caregivers attempts' to monitor youth. By offering an explicit and detailed conceptualization of monitoring, we aim to foster more rigorous and impactful research in this area.
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Relações Pais-Filho , Poder Familiar , Humanos , Criança , AdolescenteRESUMO
The gas-phase rotational spectrum from 8 to 750 GHz and the high-resolution infrared (IR) spectrum of pyridazine (o-C4H4N2) have been analyzed for the ground and four lowest-energy vibrationally excited states. A combined global fit of the rotational and IR data has been obtained using a sextic, centrifugally distorted-rotor Hamiltonian with Coriolis coupling between appropriate states. Coriolis coupling has been addressed in the two lowest-energy coupled dyads (ν16, ν13 and ν24, ν9). Utilizing the Coriolis coupling between the vibrational states of each dyad and the analysis of the IR spectrum for ν16 and ν9, we have determined precise band origins for each of these fundamental states: ν16 (B1) = 361.213 292 7 (17) cm-1, ν13 (A2) = 361.284 082 4 (17) cm-1, ν24 (B2) = 618.969 096 (26) cm-1, and ν9 (A1) = 664.723 378 4 (27) cm-1. Notably, the energy separation in the ν16-ν13 Coriolis-coupled dyad is one of the smallest spectroscopically measured energy separations between vibrational states: 2122.222 (72) MHz or 0.070 789 7 (24) cm-1. Despite ν13 being IR inactive and ν24 having an impractically low-intensity IR intensity, the band origins of all four vibrational states were measured, showcasing the power of combining the data provided by millimeter-wave and high-resolution IR spectra. Additionally, the spectra of pyridazine-dx isotopologues generated for a previous semi-experimental equilibrium structure (reSE) determination allowed us to analyze the two lowest-energy vibrational states of pyridazine for all nine pyridazine-dx isotopologues. Coriolis-coupling terms have been measured for analogous vibrational states across seven isotopologues, both enabling their comparison and providing a new benchmark for computational chemistry.
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We report the direct and accurate spectroscopic quantification of the inverted singlet-triplet gap in 1,3,4,6,9b-pentaazaphenalene. This measurement is achieved by directly probing the lowest singlet and triplet states via high-resolution cryogenic anion photoelectron spectroscopy. The assignment of the first excited singlet state is confirmed by visible absorption spectroscopy in an argon matrix at 20 K. Our measurements yield an inverted singlet-triplet gap with ΔEST= -0.047(7) eV. The accurate quantification of the singlet-triplet gap presented here allows for direct evaluation of various computational electronic structure methods and highlights the critical importance of the proper description of the double excitation character of these electronic states. Overall, this study validates the idea that despite Hund's multiplicity rule, useful organic chromophores can have inherently inverted singlet-triplet gaps.
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This study aimed to parse between-person heterogeneity in growth of impulsivity across childhood and adolescence among participants enrolled in five childhood preventive intervention trials targeting conduct problems. In addition, we aimed to test profile membership in relation to adult psychopathologies. Measurement items representing impulsive behavior across grades 2, 4, 5, 7, 8, and 10, and aggression, substance use, suicidal ideation/attempts, and anxiety/depression in adulthood were integrated from the five trials (N = 4,975). We applied latent class growth analysis to this sample, as well as samples separated into nonintervention (n = 2,492) and intervention (n = 2,483) participants. Across all samples, profiles were characterized by high, moderate, low, and low-increasing impulsive levels. Regarding adult outcomes, in all samples, the high, moderate, and low profiles endorsed greater levels of aggression compared to the low-increasing profile. There were nuanced differences across samples and profiles on suicidal ideation/attempts and anxiety/depression. Across samples, there were no significant differences between profiles on substance use. Overall, our study helps to inform understanding of the developmental course and prognosis of impulsivity, as well as adding to collaborative efforts linking data across multiple studies to better inform understanding of developmental processes.
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Broad-band ultraviolet photolysis (λ > 200 nm) of (cyanomethylene)cyclopropane (5) in an argon matrix at 20 K generates 1-cyano-2-methylenecyclopropane (7), a previously unknown compound. This product was initially identified by comparison of its infrared spectrum to that predicted by an anharmonic MP2/6-311+G(2d,p) calculation. This assignment was unambiguously confirmed by the synthesis of 1-cyano-2-methylenecyclopropane (7) and observation of its authentic infrared spectrum, which proved identical to that of the observed photoproduct. We investigated the singlet and triplet potential energy surfaces associated with this isomerization process using density functional theory and multireference calculations. The observed rearrangement of compound 5 to compound 7 is computed to be endothermic (3.3 kcal/mol). We were unable to observe the reverse reaction (7 â 5) under the photochemical conditions.
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The gas-phase rotational spectrum of 1-cyano-2-methylenecyclopropane (C1, C5H5N), an isomer of pyridine, is presented for the first time, covering the range from 235 to 500 GHz. Over 3600 a-, b-, and c-type transitions for the ground vibrational state have been assigned, measured, and least-squares fit to partial-octic A- and S-reduced distorted-rotor Hamiltonians with low statistical uncertainty (σfit = 42 kHz). Transitions for the two lowest-energy fundamental states (ν27 and ν26) and the lowest-energy overtone (2ν27) have been similarly measured, assigned, and least-squares fit to single-state Hamiltonians. Computed vibration-rotation interaction constants (B0-Bv) using the B3LYP and MP2 levels of theory are compared with the corresponding experimental values. Based upon our preliminary analysis, the next few vibrationally excited states form one or more complex polyads of interacting states via Coriolis and anharmonic coupling. The spectroscopic constants and transition frequencies presented here form the foundation for both future laboratory spectroscopy and astronomical searches for 1-cyano-2-methylenecyclopropane.
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OBJECTIVE: The authors sought to determine whether the Fast Track mental health intervention delivered to individuals in childhood decreased mental health problems and the need for health services among the children of these individuals. METHODS: The authors examined whether Fast Track assignment in one generation of children (generation 2; G2) from grades 1 through 10 reduced parent-reported mental health problems and health services use in these children's children (generation 3; G3) 18 years later relative to a control group. The Fast Track intervention blended parent behavior-management training, child social-cognitive skills tutoring, home visits, and classroom social-ecology changes across grades 1-10 to ameliorate emerging conduct problems among the G2 children. For this study, 1,057 G3 children of Fast Track participants (N=581 intervention group, N=476 control group) were evaluated. RESULTS: G3 children of G2 parents who were randomized to the Fast Track intervention group used fewer general inpatient services and fewer inpatient or outpatient mental health services compared with G3 children of G2 parents randomized to the control group. Some of these effects were mediated: randomization to Fast Track predicted fewer internalizing problems and less use of corporal punishment among G2 adults at age 25, which subsequently predicted less general inpatient service use and outpatient mental health service use among the G3 children by the time the G2 parents were 34 years old. There were no significant differences between G3 children from these two groups on the use of other health services or on mental health measures. CONCLUSIONS: Fast Track was associated with lower use of general inpatient services and inpatient and outpatient mental health services intergenerationally, but effects on parent-reported mental health of the children were not apparent across generations. Investing in interventions for the mental health of children could reduce service use burdens across generations.
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Serviços de Saúde Mental , Adulto , Criança , Humanos , Saúde Mental , Assistência Ambulatorial , Terapia Comportamental , Grupos ControleRESUMO
BACKGROUND: Across several sites in the United States, we examined whether kindergarten conduct problems among mostly population-representative samples of children were associated with increased criminal and related (criminal + lost offender productivity + victim; described as criminal + victim hereafter) costs across adolescence and adulthood, as well as government and medical services costs in adulthood. METHODS: Participants (N = 1,339) were from two multisite longitudinal studies: Fast Track (n = 754) and the Child Development Project (n = 585). Parents and teachers reported on kindergarten conduct problems, administrative and national database records yielded indexes of criminal offending, and participants self-reported their government and medical service use. Outcomes were assigned costs, and significant associations were adjusted for inflation to determine USD 2020 costs. RESULTS: A 1SD increase in kindergarten conduct problems was associated with a $21,934 increase in adolescent criminal + victim costs, a $63,998 increase in adult criminal + victim costs, a $12,753 increase in medical services costs, and a $146,279 increase in total costs. In the male sample, a 1SD increase in kindergarten conduct problems was associated with a $28,530 increase in adolescent criminal + victim costs, a $58,872 increase in adult criminal + victim costs, and a $144,140 increase in total costs. In the female sample, a 1SD increase in kindergarten conduct problems was associated with a $15,481 increase in adolescent criminal + victim costs, a $62,916 increase in adult criminal + victim costs, a $24,105 increase in medical services costs, and a $144,823 increase in total costs. CONCLUSIONS: This investigation provides evidence of the long-term costs associated with early-starting conduct problems, which is important information that can be used by policymakers to support research and programs investing in a strong start for children.
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Transtorno da Conduta , Comportamento Problema , Adulto , Criança , Humanos , Masculino , Adolescente , Feminino , Estados Unidos/epidemiologia , Transtorno da Conduta/epidemiologia , Estudos Longitudinais , Autorrelato , EscolaridadeRESUMO
The millimeter-wave rotational spectrum of 1-oxaspiro[2.5]octa-4,7-dien-6-one (1) was collected from 235 to 360 GHz. With the rotational spectrum of this compound available for the first time, more than 5500 a- and c-type transitions were observed and assigned for the vibrational ground state. These transitions were least-squares fit to S- and A-reduced, sextic distorted-rotor Hamiltonians in the Ir representation (σfit = 37 kHz). Additionally, transitions of four fundamental states (ν22, ν21, ν39, and ν38), four overtone states (2ν22, 3ν22, 4ν22, and 5ν22), and two combination states (ν22 + ν21 and ν22 + ν39) were measured, assigned, and least-squares fit to single-state, S- and A-reduced, sextic distorted-rotor Hamiltonians in the Ir representation (σfit < 42 kHz). The computed vibration-rotation interaction constants (B0 - Bv) (MP2 and B3LYP/6-311+G(2d,p)) were compared to their corresponding experimental values, showing excellent agreement for all fundamental states. Based on the intensities of the transitions from six members of the v ν22 series, the fundamental frequency of ν22 was determined to be 79.0 (2.1) cm-1.
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Photolysis (λ > 613 nm) of 1-(3-thienyl)diazoethane (21) yields the s-E rotamer of triplet 1-(3-thienyl)ethylidene (3), as characterized by UV/vis and EPR spectroscopy. The s-Z rotamer of 3 was not observed. EPR and UV/vis signals attributed to carbene 3 decrease by approximately 50% upon standing in the dark for 68 h at 10 K. Although formally spin-forbidden, an intramolecular [1,2]-hydrogen shift in triplet carbene 3 to afford singlet s-E 3-vinylthiophene (8) is presumed to occur via quantum mechanical tunneling. The behavior of the CD3 analogue supports this interpretation. Photolysis (λ > 613 nm) of 1-(3-thienyl)diazoethane-d3 (21-d3) yields triplet 1-(3-thienyl)ethylidene-d3 (3-d3), as characterized by IR, UV/vis, and EPR spectroscopy. No change in the signal intensity of EPR and UV/vis signals of triplet 3-d3 is observed upon standing in the dark for 68 h at 10 K. In a series of 2-substituted thienyl derivatives, irradiation of 1-(2-thienyl)diazoethane (22), 1-(2-thienyl)diazoethane-d3 (22-d3), or (3-methyl-2-thienyl)diazomethane (23) does not yield triplet carbene intermediates. Positioning and labeling of the methyl group proved to have a large effect on products observed for these species. 1-(2-Thienyl)diazoethane (22) yields the products of [1,2]-hydrogen migration, s-Z and s-E 2-vinylthiophene (7), while 22-d3 and 23 give products derived from opening of the thiophene ring.
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In the United States (U.S.), premature mortality in adulthood from suicide, alcohol-related disease, and substance overdoses has increased steadily over the past two decades. To better understand these trends, it is necessary to first examine the harmful behaviors that often precede these preventable deaths (i.e., suicidal ideation and attempts, and harmful alcohol and substance use). Representing critical developmental periods in which psychopathology is most likely to emerge, childhood and adolescence provide an informative lens through which to investigate susceptibility to harmful behaviors. This article synthesizes current evidence describing these rising U.S. mortality rates and the prevalence rates of harmful behaviors linked to these types of mortality. A brief selective review of longitudinal research on harmful behaviors in relation to the most relevant categories of child and adolescent psychopathology is then provided. Finally, recommendations for future research and implications for prevention are discussed.
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Comportamento do Adolescente , Transtornos Mentais , Humanos , Criança , Adolescente , Estados Unidos , Mortalidade Prematura , Ideação Suicida , Transtornos Mentais/epidemiologiaRESUMO
Recent advances in gas-phase structure determination afford outstanding agreement between the CCSD(T)/cc-pCVTZ-corrected semi-experimental (reSE) equilibrium structures and their corresponding best theoretical estimates (BTEs) of the equilibrium structures (re) based upon corrections to the CCSD(T)/cc-pCV5Z geometries for the aromatic heterocycles pyrimidine and pyridazine. Herein, that same analysis is extended to the fundamental aromatic molecule benzene, using published experimental spectroscopic data for a total of 11 available isotopologues. The incorporation of rotational constants from all of these isotopologues and CCSD(T) corrections to address the impacts of both the vibration-rotation interaction and electron-mass distribution results in a highly precise and accurate reSE structure. The CCSD(T)/cc-pCV5Z optimized geometry has been further corrected to address a finite basis set, untreated electron correlation, relativistic effects, and a breakdown of the Born-Oppenheimer approximation. This analysis achieves outstanding agreement between the re (BTE) and reSE structural parameters of benzene to a highly satisfying level (0.0001 Å), an agreement that surpasses our recently published structures of the aforementioned nitrogen-substituted benzene analogues. The D6h geometry of benzene is now known to an unprecedented precision: RC-C = 1.3913 (1) Å and RC-H = 1.0809 (1) Å. The mutual agreement between theory and experiment presented in this work validates both, substantially resolving all discrepancies between the reSE and theoretical re structures available in the literature.
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The millimeter-wave rotational spectrum of ketene (H2C=C=O) has been collected and analyzed from 130 to 750 GHz, providing highly precise spectroscopic constants from a sextic, S-reduced Hamiltonian in the Ir representation. The chemical synthesis of deuteriated samples allowed spectroscopic measurements of five previously unstudied ketene isotopologues. Combined with previous work, these data provide a new, highly precise, and accurate semi-experimental (reSE) structure for ketene from 32 independent moments of inertia. This reSE structure was determined with the experimental rotational constants of each available isotopologue, together with computed vibration-rotation interaction and electron-mass distribution corrections from coupled-cluster calculations with single, double, and perturbative triple excitations [CCSD(T)/cc-pCVTZ]. The 2σ uncertainties of the reSE parameters are ≤0.0007 Å and 0.014° for the bond distances and angle, respectively. Only S-reduced spectroscopic constants were used in the structure determination due to a breakdown in the A-reduction of the Hamiltonian for the highly prolate ketene species. All four reSE structural parameters agree with the "best theoretical estimate" (BTE) values, which are derived from a high-level computed re structure [CCSD(T)/cc-pCV6Z] with corrections for the use of a finite basis set, the incomplete treatment of electron correlation, relativistic effects, and the diagonal Born-Oppenheimer breakdown. In each case, the computed value of the geometric parameter lies within the statistical experimental uncertainty (2σ) of the corresponding semi-experimental coordinate. The discrepancies between the BTE structure and the reSE structure are 0.0003, 0.0000, and 0.0004 Å for rC-C, rC-H, and rC-O, respectively, and 0.009° for θC-C-H.
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Etilenos , Teoria Quântica , Análise Espectral , CetonasRESUMO
Coercive and disruptive behaviors commonly interfere with cognitive-behavioral therapy (CBT) trials among youths with obsessive-compulsive disorder (OCD). Although evidence supports parent management training (PMT) for reducing disruptive behavior, no group-based PMT interventions exist for OCD-related disruptive behaviors. We studied feasibility and effectiveness of group-based adjunctive PMT among non-randomized, OCD-affected families receiving family-based group CBT. Linear mixed models estimated treatment effects across OCD-related and parenting outcomes at post-treatment and 1-month follow-up. Treatment response for 37 families receiving CBT + PMT (Mage = 13.90) was compared to 80 families receiving only CBT (Mage = 13.93). CBT + PMT was highly accepted by families. Families who received CBT + PMT had improved disruptive behaviors, parental distress tolerance, and other OCD-related outcomes. OCD-related outcomes did not significantly differ between groups. Results support CBT + PMT as effective treatment for pediatric OCD that may not provide incremental benefits beyond CBT alone. Future research should determine feasible and effective ways to incorporate key PMT components into CBT-based interventions.
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We present computational studies of reaction pathways for alkyne/polyyne dimerization that represent plausible early steps in mechanisms for carbon condensation. A previous computational study of the ring coalescence and annealing model of C60 formation revealed that a 1,4-didehydrobenzocyclobutadiene intermediate (p-benzyne derivative) has little to no barrier to undergoing an unproductive retro-Bergman cyclization, which brings into question the relevance of that reaction pathway. The current study investigates an alternative model, which proceeds through an initial [4 + 2] cycloaddition instead of a [2 + 2] cycloaddition. In this pathway, the problematic intermediate is avoided, with the reaction proceeding via a (potentially) more kinetically stable tetradehydronaphthalene derivative. The computational studies of the [2 + 2] and [4 + 2] model systems, with increasing alkyne substitutions, reveal that the para-benzyne diradical of the [4 + 2] pathway has a significantly greater barrier to ring opening than the analogous intermediates of the [2 + 2] pathway and that alkyne substitution has little effect on this important barrier. These studies employ spin-flip, time-dependent density functional theory (SF-TDDFT) to provide suitable treatment of open-shell diradical intermediates.
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In this work, we present the spectral analysis of 1H- and 2H-1,2,3-triazole vibrationally excited states alongside provisional and practical computational predictions of the excited-state quartic centrifugal distortion constants. The low-energy fundamental vibrational states of 1H-1,2,3-triazole and five of its deuteriated isotopologues ([1-2H]-, [4-2H]-, [5-2H]-, [4,5-2H]-, and [1,4,5-2H]-1H-1,2,3-triazole), as well as those of 2H-1,2,3-triazole and five of its deuteriated isotopologues ([2-2H]-, [4-2H]-, [2,4-2H]-, [4,5-2H]-, and [2,4,5-2H]-2H-1,2,3-triazole), are studied using millimeter-wave spectroscopy in the 130-375 GHz frequency region. The normal and [2-2H]-isotopologues of 2H-1,2,3-triazole are also analyzed using high-resolution infrared spectroscopy, determining the precise energies of three of their low-energy fundamental states. The resulting spectroscopic constants for each of the vibrationally excited states are reported for the first time. Coupled-cluster vibration-rotation interaction constants are compared with each of their experimentally determined values, often showing agreement within 500 kHz. Newly available coupled-cluster predictions of the excited-state quartic centrifugal distortion constants based on fourth-order vibrational perturbation theory are benchmarked using a large number of the 1,2,3-triazole tautomer isotopologues and vibrationally excited states studied.
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The rotational spectrum of 2-furonitrile (2-cyanofuran) has been obtained from 140 to 750 GHz, capturing its most intense rotational transitions at ambient temperature. 2-Furonitrile is one of two isomeric cyano-substituted furan derivatives, both of which possess a substantial dipole moment due to the cyano group. The large dipole of 2-furonitrile allowed over 10â¯000 rotational transitions of its ground vibrational state to be observed and least-squares fit to partial octic, A- and S-reduced Hamiltonians with low statistical uncertainty (σfit = 40 kHz). The high-resolution infrared spectrum, obtained at the Canadian Light Source, allowed for accurate and precise determination of the band origins of its three lowest-energy fundamental modes (ν24, ν17, and ν23). Similar to other cyanoarenes, the first two fundamental modes (ν24, Aâ³, and ν17, A', for 2-furonitrile) form an a- and b-axis Coriolis-coupled dyad. More than 7000 transitions from each of these fundamental states were fit to an octic A-reduced Hamiltonian (σfit = 48 kHz), and the combined spectroscopic analysis determines fundamental energies of 160.1645522 (26) cm-1 and 171.9436561 (25) cm-1 for ν24 and ν17, respectively. The least-squares fitting of this Coriolis-coupled dyad required 11 coupling terms, Ga, GaJ, GaK, GaJJ, GaKK, Fbc, FbcJ, FbcK, Gb, GbJ, and FacK. Using both the rotational and high-resolution infrared spectra, a preliminary least-squares fit was obtained for ν23, providing its band origin of 456.7912716 (57) cm-1. The transition frequencies and spectroscopic constants provided in this work, when combined with theoretical or experimental nuclear quadrupole coupling constants, will provide the foundation for future radioastronomical searches for 2-furonitrile across the frequency range of currently available radiotelescopes.