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Supplemental material, sj-docx-1-jvm-10.1177_13567667221101406 for Pro-environmental behaviour of the residents in sensitive tourism destinations by Jiaqi Li, Timothy J. Lee, Nan Chen and Keun-Soo Park in Journal of Vacation Marketing

The recent detection of ethynyl-functionalized cyclopropenylidene (c-C₃HC₂H) has initiated the search for other functional forms of cyclopropenylidene (c-C₃H₂) in space. There is existing gas-phase rotational spectroscopic data for cyano-cyclopropenylidene (c-C₃HCN), but the present work provides the first anharmonic vibrational spectral data for that molecule, as well as the first full set of both rotational and vibrational spectroscopic data for fluoro- and chloro-cyclopropenylidenes (c-C₃HF and c-C₃HCl). All three molecules have fundamental vibrational frequencies with substantial infrared intensities. Namely, c-C₃HCN has a moderately intense fundamental frequency at 1244.4 cm⁻¹, while c-C₃HF has two large intensity modes at 1765.4 and 1125.3 cm⁻¹ and c-C₃HCl again has two large intensity modes at 1692.0 and 1062.5 cm⁻¹. All of these frequencies are well within the spectral range covered by the high-resolution EXES instrument on NASA’s Stratospheric Observatory for Infrared Astronomy (SOFIA). Further, all three molecules have dipole moments of around 3.0 D in line with c-C₃H₂, enabling them to be observed by pure rotational spectroscopy, as well. Thus, the rovibrational spectral data presented herein should assist with future laboratory studies of functionalized cyclopropenylidenes and may lead to their interstellar or circumstellar detection.

The profile of the 11.2 μm feature of the infrared (IR) cascade emission spectra of polycyclic aromatic hydrocarbon (PAH) molecules is investigated using a vibrational anharmonic method. Several factors are found to affect the profile including: the energy of the initially absorbed ultraviolet (UV) photon, the density of vibrational states, the anharmonic nature of the vibrational modes, the relative intensities of the vibrational modes, the rotational temperature of the molecule, and blending with nearby features. Each of these factors is explored independently and influence either the red or blue wing of the 11.2 μm feature. The majority impact solely the red wing, with the only factor altering the blue wing being the rotational temperature.

Nitrogen-containing ions and molecules in the gas phase have been detected in non-Earth environments such as dark molecular clouds and more recently in the atmosphere of Saturn's moon Titan. These molecules may serve as precursors to larger heterocyclic structures that provide the foundation of complex biological molecules. On Titan, molecules of m/z 66 have been detected by the Cassini mission, and species of the empirical formula C4H4N may contribute to this signature. We have characterized seven isomers of C4H4N in anionic, neutral radical, and cationic states using density functional theory. Structures were optimized using the range-separated hybrid ωB97X-V with the cc-pVTZ and aug-cc-pVTZ basis sets. Anionic and radical C4H4N favor cyclic structures with aromatic and quasi-aromatic electron arrangements, respectively. Interestingly, ionization from the radical surface to the cation induces significant changes in structural stability, and the global minimum for positively charged isomers is CH2CCHCNH+, a pseudo-linear species reminiscent of cyanoallene. Select formation pathways to these structures from Titan's existing or postulated gas-phase species, reactions that are also relevant for other astrophysical environments, are discussed. By characterizing C4H4N isomers, we have identified energetically stable anionic, radical, and cationic structures that may be present in Titan's atmosphere and dark molecular clouds.

International audience; Astrophysics advances, in part, through laboratory astrophysics studies of the underlying processes controlling the observed properties of the Cosmos. These studies encompass both theoretical and experimental research. Robust support for laboratory astrophysics is critically needed to maximize the scientific return of astronomical observations.

We are now on a clear trajectory for improvements in exoplanet observations that will revolutionize our ability to characterize their atmospheric structure, composition, and circulation, from gas giants to rocky planets. However, exoplanet atmospheric models capable of interpreting the upcoming observations are often limited by insufficiencies in the laboratory and theoretical data that serve as critical inputs to atmospheric physical and chemical tools. Here we provide an up-to-date and condensed description of areas where laboratory and/or ab initio investigations could fill critical gaps in our ability to model exoplanet atmospheric opacities, clouds, and chemistry, building off a larger 2016 white paper, and endorsed by the NAS Exoplanet Science Strategy report. Now is the ideal time for progress in these areas, but this progress requires better access to, understanding of, and training in the production of spectroscopic data as well as a better insight into chemical reaction kinetics both thermal and radiation-induced at a broad range of temperatures. Given that most published efforts have emphasized relatively Earth-like conditions, we can expect significant and enlightening discoveries as emphasis moves to the exotic atmospheres of exoplanets., Comment: Submitted as an Astro2020 Science White Paper

The current study deconstructs the process of turning heritage resources into tourism products. A case study of the Central Sector of the Imperial Citadel of Thang Long, a UNESCO World Heritage site located in the capital city of Vietnam, Hanoi, provides an in-depth understanding of the plural use of heritage. Findings from the study reveal issues of heritage dissonance inherent in the process of resource selection, interpretation, and targeting for different audiences. It is apparent that commodification cannot be separated from the politicization of heritage. In the case of heritage of national importance and international significance, politicization has been prioritized and results in diminishing the utilization of heritage for commercial purposes such as tourism., Austrian Journal of South-East Asian Studies, Vol 8 No 2 (2015): Tourism and Development

Aims. Infrared (IR) spectroscopy is a powerful tool to study molecules in space. A key issue in such analyses is understanding the effect that temperature and anharmonicity have on different vibrational bands, and thus interpreting the IR spectra for molecules under various conditions. Methods. We combined second order vibrational perturbation theory and the Wang-Landau random walk technique to produce accurate IR spectra of highly excited PAHs. We fully incorporated anharmonic effects, such as resonances, overtones, combination bands, and temperature effects. Results. The results are validated against experimental results for the pyrene molecule (C16H10). In terms of positions, widths, and relative intensities of the vibrational bands, our calculated spectra are in excellent agreement with gas-phase experimental data.

In this work we report on high-resolution IR absorption studies that provide a detailed view on how the peripheral structure of irregular polycyclic aromatic hydrocarbons (PAHs) affects the shape and position of their 3 {\mu}m absorption band. To this purpose we present mass-selected, high-resolution absorption spectra of cold and isolated phenanthrene, pyrene, benz[a]antracene, chrysene, triphenylene, and perylene molecules in the 2950-3150 cm-1 range. The experimental spectra are compared with standard harmonic calculations, and anharmonic calculations using a modified version of the SPECTRO program that incorporates a Fermi resonance treatment utilizing intensity redistribution. We show that the 3 {\mu}m region is dominated by the effects of anharmonicity, resulting in many more bands than would have been expected in a purely harmonic approximation. Importantly, we find that anharmonic spectra as calculated by SPECTRO are in good agreement with the experimental spectra. Together with previously reported high-resolution spectra of linear acenes, the present spectra provide us with an extensive dataset of spectra of PAHs with a varying number of aromatic rings, with geometries that range from open to highly-condensed structures, and featuring CH groups in all possible edge configurations. We discuss the astrophysical implications of the comparison of these spectra on the interpretation of the appearance of the aromatic infrared 3 {\mu}m band, and on features such as the two-component emission character of this band and the 3 {\mu}m emission plateau., Comment: Accepted for publication on The Astrophysical Journal

In this work we report on high-resolution IR absorption studies that provide a detailed view on how the peripheral structure of irregular polycyclic aromatic hydrocarbons (PAHs) affects the shape and position of their 3 ��m absorption band. To this purpose we present mass-selected, high-resolution absorption spectra of cold and isolated phenanthrene, pyrene, benz[a]antracene, chrysene, triphenylene, and perylene molecules in the 2950-3150 cm-1 range. The experimental spectra are compared with standard harmonic calculations, and anharmonic calculations using a modified version of the SPECTRO program that incorporates a Fermi resonance treatment utilizing intensity redistribution. We show that the 3 ��m region is dominated by the effects of anharmonicity, resulting in many more bands than would have been expected in a purely harmonic approximation. Importantly, we find that anharmonic spectra as calculated by SPECTRO are in good agreement with the experimental spectra. Together with previously reported high-resolution spectra of linear acenes, the present spectra provide us with an extensive dataset of spectra of PAHs with a varying number of aromatic rings, with geometries that range from open to highly-condensed structures, and featuring CH groups in all possible edge configurations. We discuss the astrophysical implications of the comparison of these spectra on the interpretation of the appearance of the aromatic infrared 3 ��m band, and on features such as the two-component emission character of this band and the 3 ��m emission plateau., Accepted for publication on The Astrophysical Journal

The stability of the five main isomers of C6H3(+) was investigated using quantum chemical calculations. The cyclic isomers are stabilized by two complementary aromatic effects, first 6-electron π aromaticity, and second a more unusual three-center two-electron σ aromaticity. Two cyclic isomers sit at the bottom of the potential energy surface with energies very close to each other, with a third cyclic isomer slightly higher. The reaction barriers for the interconversion of these isomers, as well as to convert to low-energy linear isomers, are found to be very high with transition states that break both the π and the σ aromaticities. Finally, possibilities for forming the cyclic isomers via association reactions are discussed.

Very recently, molecular rotational transitions observed in the photon-dominated region of the Horsehead nebula have been attributed to l-C3H+. In an effort to corroborate this finding, we employed state-of-the art and proven high-accuracy quantum chemical techniques to compute spectroscopic constants for this cation and its isotopologues. Even though the B rotational constant from the fit of the observed spectrum and our computations agree to within 20 MHz, a typical level of accuracy, the D rotational constant differs by more than 40%, while the H rotational constant differs by three orders of magnitude. With the likely errors in the rotational transition energies resulting from this difference in D on the order of 1 MHz for the lowest observed transition (J = 4

It has been shown that rotational lines observed in the Horsehead nebula PDR are probably not caused by l-C3H+, as was originally suggested. In the search for viable alternative candidate carriers, quartic force fields are employed here to provide highly accurate rotational constants, as well as fundamental vibrational frequencies, for another candidate carrier: 1 ^1A' C3H-. The ab initio computed spectroscopic constants provided in this work are, compared to those necessary to define the observed lines, as accurate as the computed spectroscopic constants for many of the known interstellar anions. Additionally, the computed Deff for C3H- is three times closer to the D deduced from the observed Horsehead nebula lines relative to l-C3H+. As a result, 1 ^1A' C3H- is a more viable candidate for these observed rotational transitions. It has been previously proposed that at least C6H- may be present in the Horsehead nebular PDR formed by way of radiative attachment through its dipole-bound excited state. C3H- could form in a similar way through its dipole-bound state, but its valence excited state increases the number of relaxation pathways possible to reach the ground electronic state. In turn, the rate of formation for C3H- could be greater than the rate of its destruction. C3H- would be the seventh confirmed interstellar anion detected within the past decade and the first CnH- molecular anion with an odd n., Comment: 26 pages, 1 figure, 4 tables

From large basis set coupled cluster calculations and a minor empirical adjustment, an anharmonic force field for silane has been derived that is consistently of spectroscopic quality ($\pm 1 cm^{-1}$ on vibrational fundamentals) for all isotopomers of silane studied. Inner-shell polarization functions have an appreciable effect on computed properties and even on anharmonic corrections. From large basis set coupled cluster calculations and extrapolations to the infinite-basis set limit, we obtain TAE_0=303.80 \pm 0.18 kcal/mol, which includes an anharmonic zero-point energy (19.59 kcal/mol), inner-shell correlation (-0.36 kcal/mol), scalar relativistic corrections (-0.70 kcal/mol), and atomic spin-orbit corrections (-0.43 kcal/mol). In combination with the recently revised \HVSI{0}, we obtain $\Delta H^{\circ}_{f,0}[SiH_4(g)]=9.9 \pm 0.4 kcal/mol$, in between the two established experimental values., Comment: Mol. Phys., in press

A number of recently proposed single-reference open-shell perturbation theories based on a spin-restricted open-shell Hartree-Fock reference function are examined, with an emphasis on a consistent formalism within which the theories may be compared. In particular, the effect of unitary transformations among the molecular orbitals on the energy is discussed. Of the seven different perturbation theories examined here, the restricted Mo&slas;;ller–Plesset theory, open-shell perturbation theory method 1, the method of Hubacˇ and Cˇa´rsky, Z-averaged perturbation theory, and invariant open-shell perturbation theory methods are found to be invariant to all types of rotations for which the reference wave function is unaffected, though all are invariant to transformations of a more limited nature. Explicit equations for the generalized invariant forms of each perturbation theory are presented, in order to provide working equations for extension of the theories to local correlation schemes or coupled-cluster perturbational corrections, among others.

A key cause of poor system performance is inherently due to the lack of understanding of system behavior. Performance problems are especially apparent in parallel and distributed programs, for which expected speedup is difficult to achieve. Theoretical models and trace visualization tools are suitable for extracting insights into the behavior of a system. Theoretical models available today work for certain types of systems and require possibly unrealistic assumptions, and hence are not considered here. Existing trace visualization tools have yielded new insights into the behavior of the sequential, parallel, and distributed programs. However, they have two inherent limitations: (1) Each tool visualizes only one execution of a program. (This is dangerous when analyzing concurrent programs, which are prone to non-deterministic behavior.) (2) The applicable domain of a visualization tool will be limited unless the tool incorporates a large variety of methods to visually display data. This is because a single display method may yield new insights into only certain systems. In addition, finding the "right" display that can provide the needed insights is a potentially time-consuming process. This project carries through the previous work-CHITRA92. This project addresses these limitations by providing the following four capabilities to analyze traces: (1) CHITRA93 analyzes a set (or ensemble) of traces to obtain the typical behavior of a system. (2) CHITRA93 incorporates three transforms to simplify ensembles by reducing either the state space size or the interval over which time is defined in the ensemble. (3) CHITRA93 builds compact summary of the dynamic behavior (or model) of a system from an ensemble. (4) CHITRA93, to avoid building models that poorly fit an ensemble, provides a suite of methods to partition ensembles into mutually exclusive, exhaustive, and homogeneous subsets so that each subset displays "similar" behavior. These methods include several visual techniques and statistical methods. Finally, a portion of the project seeks to stabilize and to produce a correct version of CHITRA. Master of Science

Recently the presence and radiative decay of vibrationally excited CH - 2, generated in a hot cathode discharge of methane, was established by measuring the time dependent photodetachment from excited states of CH - 2 as it radiatively relaxed in a high vacuum ion trap. The time dependence of the photodetachment was found to be consistent with an electron affinity of 5250 cm^−1 (0.65 eV) for ground state X-tilde 3B1 methylene. The radiative decay lifetimes of the first three excited bending vibrations of CH - 2 were also tentatively assigned. Here, we report a more refined analysis of the experimental data along with theoretical ab initio determinations of the radiative decay lifetimes of the first four excited bending vibrational levels of CH - 2. There is some discrepancy between the ab initio values (431, 207, 118, and 68 ms for the v2=1, 2, 3, and 4 levels respectively) and the experimental values (525, 70, and 14 ms for v2=1, 2, and 3 respectively) for v2=2 and 3. Possible reasons for this discrepancy are discussed but none of the alternatives are entirely satisfactory.

22 pags., 8 figs., 1 tab., Massive stars disrupt their natal molecular cloud material through radiative and mechanical feedback processes. These processes have profound effects on the evolution of interstellar matter in our Galaxy and throughout the universe, from the era of vigorous star formation at redshifts of 1-3 to the present day. The dominant feedback processes can be probed by observations of the Photo-Dissociation Regions (PDRs) where the far-ultraviolet photons of massive stars create warm regions of gas and dust in the neutral atomic and molecular gas. PDR emission provides a unique tool to study in detail the physical and chemical processes that are relevant for most of the mass in inter-and circumstellar media including diffuse clouds, proto-planetary disks, and molecular cloud surfaces, globules, planetary nebulae, and star-forming regions. PDR emission dominates the infrared (IR) spectra of star-forming galaxies. Most of the Galactic and extragalactic observations obtained with the James Webb Space Telescope (JWST) will therefore arise in PDR emission. In this paper we present an Early Release Science program using the MIRI, NIRSpec, and NIRCam instruments dedicated to the observations of an emblematic and nearby PDR: the Orion Bar. These early JWST observations will provide template data sets designed to identify key PDR characteristics in JWST observations. These data will serve to benchmark PDR models and extend them into the JWST era. We also present the Science-Enabling products that we will provide to the community. These template data sets and Science-Enabling products will guide the preparation of future proposals on star-forming regions in our Galaxy and beyond and will facilitate data analysis and interpretation of forthcoming JWST observations., Support for JWST-ERS program ID 1288 was provided through grants from the STScI under NASA contract NAS5-03127 to STScI (K.G., D.V.D.P., M.R.), Univ. of Maryland (M.W., M.P.), Univ. of Michigan (E.B., F.A.), and Univ. of Toledo (T.S.-Y.L.). O.B. and E.H. are supported by the Programme National “Physique et Chimie du Milieu Interstellaire” (PCMI) of CNRS/INSU with INC/INP co-funded by CEA and CNES, and through APR grants 6315 and 6410 provided by CNES. E. P. and J.C. acknowledge support from the National Science and Engineering Council of Canada (NSERC) Discovery Grant program (RGPIN-2020-06434 and RGPIN-2021-04197 respectively). E.P. acknowledges support from a Western Strategic Support Accelerator Grant (ROLA ID 0000050636). J.R.G. and S.C. thank the Spanish MCINN for funding support under grant PID2019-106110GB-I00. Work by M.R. and Y.O. is carried out within the Collaborative Research Centre 956, subproject C1, funded by the Deutsche Forschungsgemeinschaft (DFG)—project ID 184018867. T.O. acknowledges support from JSPS Bilateral Program, grant No. 120219939. M.P. and M.W. acknowledge support from NASA Astrophysics Data Analysis Program award #80NSSC19K0573. C.B. is grateful for an appointment at NASA Ames Research Center through the San José State University Research Foundation (NNX17AJ88A) and acknowledges support from the Internal Scientist Funding Model (ISFM) Directed Work Package at NASA Ames titled: “Laboratory Astrophysics—The NASA Ames PAH IR Spectroscopic Database.”

The dipole moment, polarizabilities and hyperpolarizabilities of Ne, Be, BH, CH+, CO and NNO have been determined using the coupled-cluster and Brueckner coupled-cluster methods. The effect of orbital relaxation on these properties has been investigated implicitly, by carrying out singles and doubled coupled-cluster (CCSD) calculations with and without field relaxed SCF orbitals and explicitly through carrying out Brueckner doubles (BCCD) calculations. The effect of the connected triple excitations has been considered in the methods CCSD(T) and BCCD(T). The results show that allowing the SCF orbitals to relax in the presence of the field can make a significant difference to the CCSD properties. It has also been found that CCSD with field relaxed SCF orbitals and BCCD give similar results.