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Littérature scientifique sur le sujet « Interstellar organic complex molecules iCOMS »

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Publié le 10 mars 2023

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Articles de revues sur le sujet "Interstellar organic complex molecules iCOMS"

Rojas-García, O. S., A. I. Gómez-Ruiz, A. Palau, M. T. Orozco-Aguilera, M. Chavez Dagostino et S. E. Kurtz. « Interstellar Complex Organic Molecules in SiO-traced Massive Outflows ». Astrophysical Journal Supplement Series 262, n^o 1 (19 août 2022) : 13. http://dx.doi.org/10.3847/1538-4365/ac81cb.

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Abstract The interstellar medium contains dust and gas, in which molecules can proliferate at high densities and in cold conditions. Interstellar complex organic molecules (iCOMs) are C-bearing species that contain at least six atoms. As they are detected in young stellar objects, iCOMs are expected to inhabit early stages of star formation evolution. In this study, we try to determine which iCOMs are present in the outflow component of massive protostars. To do this, we analyzed the morphological extension of blue- and redshifted iCOM emission in a sample of 11 massive protostars employing mapping observations at 1 mm within a ∼1 GHz bandwidth for both the IRAM-30 m and APEX telescopes. We modeled the iCOM emission of the central pointing spectra of our objects using the XCLASS local thermal equilibrium radiative transfer code. We detected the presence of several iCOMs such as CH3OH, 13CH3OH, CH3OCHO, C2H5C15N, and (c-C3H2)CH2. In G034.41+0.24, G327.29-0.58, G328.81+0.63, G333.13-0.43, G340.97-1.02, G351.45+0.66, and G351.77-0.54, the iCOM lines show a faint broad-line profile. Due to the offset peak positions of the blue- and redshifted emission, covering from ∼0.1 to 0.5 pc, these wings are possibly related to movements external to the compact core, such as large-scale low-velocity outflows. We have also established a correlation between the parent iCOM molecule CH3OH and the shock tracer SiO, reinforcing the hypothesis that shock environments provide the conditions to boost the formation of iCOMs via gas-phase reactions.

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Vazart, Fanny, Cecilia Ceccarelli, Nadia Balucani et Dimitrios Skouteris. « Quantum Chemical Computations of Gas-phase Glycolaldehyde Deuteration and Constraints on Its Formation Route ». Astrophysical Journal 941, n^o 2 (1 décembre 2022) : 196. http://dx.doi.org/10.3847/1538-4357/aca3a3.

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Abstract Despite the detection of numerous interstellar complex organic molecules (iCOMs) for decades, it is still a matter of debate whether they are synthesized in the gas phase or on the icy surface of interstellar grains. In the past, molecular deuteration has been used to constrain the formation paths of small and abundant hydrogenated interstellar species. More recently, the deuteration degree of formamide, one of the most interesting iCOMs, has also been explained with the hypothesis that it is formed by the gas-phase reaction NH2 + H2CO. In this paper, we aim at using molecular deuteration to constrain the formation of another iCOM, glycolaldehyde, which is an important prebiotic species. More specifically, we have performed dedicated electronic structure and kinetic calculations to establish the glycolaldehyde deuteration degree in relation to that of ethanol, which is its possible parent species according to the suggestion of Skouteris et al. We found that the abundance ratio of the species containing one D atom over the all-protium counterpart depends on the produced D isotopomer and varies from 0.9 to 0.5. These theoretical predictions compare extremely well with the monodeuterated isotopomers of glycolaldehyde and that of ethanol measured toward the solar-like protostar IRAS 16293–2422, supporting the hypothesis that glycolaldehyde could be produced in the gas phase for this source. In addition, the present work confirms that the deuterium fractionation of iCOMs cannot be simply anticipated based on the deuterium fractionation of the parent species but necessitates a specific study, as already shown for the case of formamide.

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Bianchi, Eleonora. « Interstellar complex organic molecules in the prototypical Class I protostar SVS13-A : From large scales to planet forming disks ». EPJ Web of Conferences 265 (2022) : 00028. http://dx.doi.org/10.1051/epjconf/202226500028.

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We present a chemical systematic study of the Class I object SVS13- A obtained in the framework of two IRAM Large Programs: ASAI (Astrochemical Survey At IRAM-30m) with the 30m and SOLIS (Seeds Of Life In Space) with NOEMA. Thanks to the ASAI high-sensitivity unbiased spectral survey of the 3, 2 and 1.3mm bands, we detect and analyse several emission lines from deuterated species and interstellar complex organic molecules (iCOMs, e.g. molecules composed by 6 or more atoms and based on carbon). Within SOLIS, we obtain high-sensitivity and high-spatial resolution (∼ 180 au) maps of crucial iCOMs. As a follow up, thanks to ALMA we explore the chemistry in the planet forming region (∼ 50 au). We image emission lines from methanol (CH3OH), acetaldehyde (CH3CHO), formamide (NH2CHO) and dimethyl ether (CH3OCH3). The different spatial distributions suggest a chemical differentiation inside the binary system or a different continuum opacity in the two protostellar disks.

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López-Sepulcre, Ana, et Mathilde Bouvier. « Molecular richness in protostars : Lessons learnt from spectral observations ». EPJ Web of Conferences 265 (2022) : 00026. http://dx.doi.org/10.1051/epjconf/202226500026.

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The gas associated with the early stages of star formation contains traces of a large variety of molecular species, many of which are organic in nature. Interestingly, we observe a substantial chemical diversity among protostars, with some objects being enriched in what astrochemists label interstellar complex organic molecules (iCOMs), such as methyl formate (HCOOCH3), while others are overabundant in unsaturated carbon chains such as C4H. What is the cause of this diversity? And where should we place the proto-solar-system in this chemical context: was it rich in iCOMs, or in carbon chains, or in both? Thanks to the development of sensitive broadband (sub-)millimetre instrumentation, both in single-dish telescopes and interferometers, we are currently witnessing big steps forward in this area. The present contribution summarises what we have learnt, in the past decade or so, about the molecular contents in solar-mass protostellar sources, and suggests a few guidelines to stimulate progress in the field.

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Enrique-Romero, Joan, Albert Rimola, Cecilia Ceccarelli, Piero Ugliengo, Nadia Balucani et Dimitrios Skouteris. « Quantum Mechanical Simulations of the Radical–Radical Chemistry on Icy Surfaces ». Astrophysical Journal Supplement Series 259, n^o 2 (22 mars 2022) : 39. http://dx.doi.org/10.3847/1538-4365/ac480e.

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Abstract The formation of the interstellar complex organic molecules (iCOMs) is a hot topic in astrochemistry. One of the main paradigms trying to reproduce the observations postulates that iCOMs are formed on the ice mantles covering the interstellar dust grains as a result of radical–radical coupling reactions. We investigate iCOM formation on the icy surfaces by means of computational quantum mechanical methods. In particular, we study the coupling and direct hydrogen abstraction reactions involving the CH3 + X systems (X = NH2, CH3, HCO, CH3O, CH2OH) and HCO + Y (Y = HCO, CH3O, CH2OH), plus the CH2OH + CH2OH and CH3O + CH3O systems. We computed the activation energy barriers of these reactions, as well as the binding energies of all the studied radicals, by means of density functional theory calculations on two ice water models, made of 33 and 18 water molecules. Then, we estimated the efficiency of each reaction using the reaction activation, desorption, and diffusion energies and derived kinetics with the Eyring equations. We find that radical–radical chemistry on surfaces is not as straightforward as usually assumed. In some cases, direct H-abstraction reactions can compete with radical–radical couplings, while in others they may contain large activation energies. Specifically, we found that (i) ethane, methylamine, and ethylene glycol are the only possible products of the relevant radical–radical reactions; (ii) glyoxal, methyl formate, glycolaldehyde, formamide, dimethyl ether, and ethanol formation is likely in competition with the respective H-abstraction products; and (iii) acetaldehyde and dimethyl peroxide do not seem to be likely grain-surface products.

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Puzzarini, Cristina, Zoi Salta, Nicola Tasinato, Jacopo Lupi, Carlo Cavallotti et Vincenzo Barone. « A twist on the reaction of the CN radical with methylamine in the interstellar medium : new hints from a state-of-the-art quantum-chemical study ». Monthly Notices of the Royal Astronomical Society 496, n^o 4 (16 juin 2020) : 4298–310. http://dx.doi.org/10.1093/mnras/staa1652.

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ABSTRACT Despite the fact that the majority of current models assume that interstellar complex organic molecules (iCOMs) are formed on dust–grain surfaces, there is some evidence that neutral gas-phase reactions play an important role. In this paper, we investigate the reaction occurring in the gas phase between methylamine (CH3NH2) and the cyano (CN) radical, for which only fragmentary and/or inaccurate results have been reported to date. This case study allows us to point out the pivotal importance of employing quantum-chemical calculations at the state of the art. Since the two major products of the CH3NH2 + CN reaction, namely the CH3NH and CH2NH2 radicals, have not been spectroscopically characterized yet, some effort has been made for filling this gap.

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Chahine, L., A. López-Sepulcre, R. Neri, C. Ceccarelli, S. Mercimek, C. Codella, M. Bouvier et al. « Organic chemistry in the protosolar analogue HOPS-108 : Environment matters ». Astronomy & ; Astrophysics 657 (janvier 2022) : A78. http://dx.doi.org/10.1051/0004-6361/202141811.

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Context. Hot corinos are compact regions around solar-mass protostellar objects that are very rich in interstellar Complex Organic Molecules (iCOMs). How the abundance of these molecules is affected by the environmental physical conditions is still an open question. More specifically, addressing this point is key to understand our own chemical origins since the Solar System formed in a large cluster of low- to high-mass stars and was therefore subject to external heating and ultraviolet irradiation which may have shaped the chemistry of its early formation stages. Aims. The goal of this high resolution study is to determine the abundance ratios of iCOMs in HOPS-108, which is a Class 0 protostar and a hot corino candidate located in the nearest Solar System analogue, the protostellar cluster OMC-2 FIR 4, in Orion. We aim to compare the abundance ratios to those found in other hot corinos, which are all located in less crowded environments, in order to understand the impact of environmental conditions on hot corinos’ chemistry. Methods. We observed the OMC-2 FIR 4 proto-cluster using the Band 6 of the Atacama Large (sub-)Millimetre Array in Cycle 4 with an angular resolution of ~0.′′28 (110 au). We determined the abundances and temperature of the species using local thermodynamic equilibrium (LTE) and non-LTE analysis. Results. Our results reveal a rich organic chemistry towards HOPS-108, asserting that it is a hot corino where the following iCOMs are detected: CH3OH, HCOOCH3, CH3OCH3, CH318OH, CH2DOH, CH3COCH3, CH3CHO, CH3CN, 13CH3CN, C2H5CN, and NH2CHO. Remarkably, we find a possible enhancement in the HCOOCH3 abundance with respect to other known hot corinos. Indeed, the [CH3OCH3]/[HCOOCH3] abundance ratio in this source is ~0.2 and, within the uncertainties, it deviates from the known correlation marginally where [CH3OCH3]/[HCOOCH3] ~1. A relatively low [CH2DOH]/[CH3OH] abundance ratio of ~0.02 is also obtained, which is in agreement with that found in another Orion source, HH212, suggesting a higher gas temperature during the early phases of ice mantle formation. Conclusions. The [CH3OCH3]/[HCOOCH3] and [CH2DOH]/[CH3OH] abundance ratios in HOPS-108 might result from different physical conditions in the Orion molecular complex compared to other regions. The former ratio cannot be reproduced with current chemical models, highlighting the importance of improving the chemical networks with theoretical calculations. More hot corinos located in heavily clustered regions such as Orion should be targeted in order to measure these ratios and evaluate whether they are an environmental product or whether HOPS-108 is an exceptional hot corino overall.

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Imai, Muneaki, Yoko Oya, Brian Svoboda, Hauyu Baobab Liu, Bertrand Lefloch, Serena Viti, Yichen Zhang et al. « Chemical and Physical Characterization of the Isolated Protostellar Source CB68 : FAUST IV ». Astrophysical Journal 934, n^o 1 (1 juillet 2022) : 70. http://dx.doi.org/10.3847/1538-4357/ac77e7.

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Abstract The chemical diversity of low-mass protostellar sources has so far been recognized, and environmental effects are invoked as its origin. In this context, observations of isolated protostellar sources without the influence of nearby objects are of particular importance. Here, we report the chemical and physical structures of the low-mass Class 0 protostellar source IRAS 16544−1604 in the Bok globule CB 68, based on 1.3 mm Atacama Large Millimeter/submillimeter Array observations at a spatial resolution of ∼70 au that were conducted as part of the large program FAUST. Three interstellar saturated complex organic molecules (iCOMs), CH3OH, HCOOCH3, and CH3OCH3, are detected toward the protostar. The rotation temperature and the emitting region size for CH3OH are derived to be 131 ± 11 K and ∼10 au, respectively. The detection of iCOMs in close proximity to the protostar indicates that CB 68 harbors a hot corino. The kinematic structure of the C18O, CH3OH, and OCS lines is explained by an infalling–rotating envelope model, and the protostellar mass and the radius of the centrifugal barrier are estimated to be 0.08–0.30 M ⊙ and <30 au, respectively. The small radius of the centrifugal barrier seems to be related to the small emitting region of iCOMs. In addition, we detect emission lines of c-C3H2 and CCH associated with the protostar, revealing a warm carbon-chain chemistry on a 1000 au scale. We therefore find that the chemical structure of CB 68 is described by a hybrid chemistry. The molecular abundances are discussed in comparison with those in other hot corino sources and reported chemical models.

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Ascenzi, Daniela, Andrea Cernuto, Nadia Balucani, Paolo Tosi, Cecilia Ceccarelli, Luca Matteo Martini et Fernando Pirani. « Destruction of dimethyl ether and methyl formate by collisions with He+ ». Astronomy & ; Astrophysics 625 (mai 2019) : A72. http://dx.doi.org/10.1051/0004-6361/201834585.

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Context. To correctly model the abundances of interstellar complex organic molecules (iCOMs) in different environments, both formation and destruction routes should be appropriately accounted for. While several scenarios have been explored for the formation of iCOMs via grain and gas-phase processes, much less work has been devoted to understanding the relevant destruction pathways, with special reference to (dissociative) charge exchange or proton transfer reactions with abundant atomic and molecular ions such as He+, H3+ and HCO+. Aims. By using a combined experimental and theoretical methodology we provide new values for the rate coefficients and branching ratios (BRs) of the reactions of He+ ions with two important iCOMs, namely dimethyl ether (DME) and methyl formate (MF). We also review the destruction routes of DME and MF by other two abundant ions, namely H3+ and HCO+. Methods. Based on our recent laboratory measurements of cross sections and BRs for the DME/MF + He+ reactions over a wide collision energy, we extended our theoretical insights on the selectivity of the microscopic dynamics to calculate the rate coefficients k(T) in the temperature range from 10 to 298 K. We implemented these new and revised kinetic data in a general model of cold and warm gas, simulating environments where DME and MF have been detected. Results. Due to stereodynamical effects present at low collision energies, the rate coefficients, BRs and temperature dependences here proposed differ substantially from those reported in KIDA and UDfA, two of the most widely used astrochemical databases. These revised rates impact the predicted abundances of DME and MF, with variations up to 40% in cold gases and physical conditions similar to those present in prestellar cores. Conclusions. This work demonstrates that the accuracy of astrochemical models can be improved by a thorough characterisation of the destruction routes of iCOMs. The details of the chemical systems can, indeed, strongly affect their efficiency and significant deviations with respect to the commonly used Langevin model estimates are possible.

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De Simone, M., C. Codella, C. Ceccarelli, A. López-Sepulcre, A. Witzel, R. Neri, N. Balucani et al. « Seeds of Life in Space (SOLIS) ». Astronomy & ; Astrophysics 640 (août 2020) : A75. http://dx.doi.org/10.1051/0004-6361/201937004.

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Context. The interstellar complex organic molecules (iCOMs) are C-bearing molecules containing at least six atoms; two main proposals for their formation are suggested: a direct formation in the icy mantle of the dust grains and formation through the reaction in gas phase of released grain mantle species. The shocked gas along outflows driven by low-mass protostars is a unique environment to study how the iCOMs can be formed as the composition of the dust mantles is sputtered into the gas phase. Aims. The chemical richness in shocked material associated with low-mass protostellar outflows has been so far studied in the prototypical L1157 blue-shifted outflow to investigate the iCOM formation routes. To understand whether the case of L1157-B1 is unique, we imaged and studied the IRAS 4A outflows in the NGC 1333 star forming region. Methods. We used the NOrthern Extended Millimeter Array interferometer as part of the IRAM Seeds Of Life in Space (SOLIS) Large Program to image the large-scale bipolar outflows driven by the IRAS 4A system in the 3 mm band, and we compared the observation with the GRAINOBLE+ astrochemical model. Results. We report the first detection, in the IRAS 4A outflows, of several iCOMs: six lines of methanol (CH3OH), eight of acetaldehyde (CH3CHO), one of formamide (NH2CHO), and four of dimethyl ether (CH3OCH3), all sampling upper excitation energy up to ~30 K. We found a significant chemical differentiation between the southeast outflow driven by the IRAS 4A1 protostar, showing a richer molecular content, and the north–southwest one driven by the IRAS 4A2 hot corino. The CH3OH/CH3CHO abundance ratio is lower by a factor of ~4 in the former; furthermore, the ratio in the IRAS 4A outflows is lower by a factor of ~10 with respect to the values found in different hot corinos. Conclusions. After L1157-B1, the IRAS 4A outflow is now the second outflow to show an evident chemical complexity. Given that CH3OH is a grain surface species, the astrochemical gas-phase model run with GRAINOBLE+ reproduced our observation assuming that acetaldehyde is formed mainly through the gas-phase reaction of the ethyl radical (CH3CH2) and atomic oxygen. Furthermore, the chemical differentiation between the two outflows suggests that the IRAS 4A1 outflow is likely younger than that of the IRAS 4A2. Further investigation is needed to constrain the age of the outflow. In addition, observation of even younger shocks are necessary. In order to provide strong constraints on the CH3CHO formation mechanisms it would be interesting to observe CH3CH2, but given that its frequencies are not known, future spectroscopic studies on this species are needed.

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Thèses sur le sujet "Interstellar organic complex molecules iCOMS"

Vazart, Fanny. « Gas-phase formation of Complex Organic Models molecules in interstellar medium : computational investigations ». Doctoral thesis, Scuola Normale Superiore, 2017. http://hdl.handle.net/11384/85813.

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[excerpt form the abstract:] In the field of astro- and prebiotic chemistry, the building blocks of life, which are molecules composed of more than 6 atoms, are called Complex Organic Molecules (COMs). Their appearances on the early inorganic Earth is therefore one of the major issues faced by researchers interested in the origin of life. In this thesis, split into three parts, the main purpose is to show how different COMs are formed in interstellar medium (ISM), using computational chemistry. The first part focuses mainly on preliminary studies aiming at evaluating the appropriate level of theory to use to perform studies of formation reactions. First, a comprehensive benchmark of C≡N stretching vibrations computed at harmonic and anharmonic levels is reported with the goal of proposing and validating a reliable computational strategy to get accurate results for this puzzling vibrational mode, involved in biological molcules, without any ad hoc scaling factor.

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Corazzi, Maria Angela. « Laboratory studies on photoprocessing and desorption of prebiotic molecules in space ». Doctoral thesis, 2022. http://hdl.handle.net/2158/1264298.

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This Ph.D. project was developed within the research projects of astrobiology “Space life- OPPS” and “Reservoirs for Planetary Atmospheres”. The project was focused on laboratory studies on photoprocessing and thermal desorption of formamide (HCONH2), acetonitrile (CH3CN), and acetaldehyde (CH3COH) in simulated space conditions. The analytical techniques used were Fourier Transformed Infrared Spectroscopy (FTIR), Temperature Programmed Desorption (TPD) analysis, and mass spectroscopy.

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Chapitres de livres sur le sujet "Interstellar organic complex molecules iCOMS"

Kakkar, Harjasnoor, Berta Martínez-Bachs et Albert Rimola. « An Ab Initio Computational Study of Binding Energies of Interstellar Complex Organic Molecules on Crystalline Water Ice Surface Models ». Dans Computational Science and Its Applications – ICCSA 2022 Workshops, 281–92. Cham : Springer International Publishing, 2022. http://dx.doi.org/10.1007/978-3-031-10562-3_21.

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AbstractThe interstellar medium is extremely heterogeneous in terms of physical environments and chemical composition. Spectroscopic observations in the recent decades have revealed the presence of gaseous material and dust grains covered in ices predominantly of water in interstellar clouds, the interplay of which may elucidate the existence of more than 250 molecular species. Of these species of varied complexity, several terrestrial carbon-containing compounds have been discovered, known as interstellar complex organic molecules (iCOMs) in the astrochemical argot. In order to investigate the formation of iCOMs, it is crucial to explore gas-grain chemistry and in this regard, one of the fundamental parameters is the binding energy (BE), which is an essential input in astrochemical models. In this work, the BEs of 13 iCOMs on a crystalline H2O-ice surface have been computed by means of quantum chemical periodic calculations. The hybrid B3LYP-D3 DFT method was used for the geometry optimizations of the adsorbate/ice systems and for computing the BEs. Furthermore, to refine the BE values, an ONIOM2-like approximation has been employed to obtain them at CCSD(T), which correlate well with those obtained at B3LYP-D3. Additionally, aiming to lower the computational cost, structural optimizations were carried out using the HF-3c level of theory, followed by single point energy calculations at B3LYP-D3 in order to obtain BE values comparable to the full DFT treatment.

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Germain, Aurèle, Marta Corno et Piero Ugliengo. « Computing Binding Energies of Interstellar Molecules by Semiempirical Quantum Methods : Comparison Between DFT and GFN2 on Crystalline Ice ». Dans Computational Science and Its Applications – ICCSA 2021, 632–45. Cham : Springer International Publishing, 2021. http://dx.doi.org/10.1007/978-3-030-86976-2_43.

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AbstractInterstellar Grains (IGs) spread in the Interstellar Medium (ISM) host a multitude of chemical reactions that could lead to the production of interstellar Complex Organic Molecules (iCOMs), relevant in the context of prebiotic chemistry. These IGs are composed of a silicate-based core covered by several layers of amorphous water ice, known as a grain mantle. Molecules from the ISM gas-phase can be adsorbed at the grain surfaces, diffuse and react to give iCOMs and ultimately desorbed back to the gas phase. Thus, the study of the Binding Energy (BE) of these molecules at the water ice grain surface is important to understand the molecular composition of the ISM and its evolution in time. In this paper, we propose to use a recently developed semiempirical quantum approach, named GFN-xTB, and more precisely the GFN2 method, to compute the BE of several molecular species at the crystalline water ice slab model. This method is very cheap in term of computing power and time and was already showed in a previous work to be very accurate with small water clusters. To support our proposition, we decided to use, as a benchmark, the recent work published by some of us in which a crystalline model of proton-ordered water ice (P-ice) was adopted to predict the BEs of 21 molecules relevant in the ISM. The relatively good results obtained confirm GFN2 as the method of choice to model adsorption processes occurring at the icy grains in the ISM. The only notable exception was for the CO molecule, in which both structure and BE are badly predicted by GFN2, a real pity due to the relevance of CO in astrochemistry.

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Greenberg, J. Mayo, et Willem Schutte. « Infrared Spectral Identification of Complex Organic Molecules in Interstellar Grains ». Dans The Search for Extraterrestrial Life : Recent Developments, 145–50. Dordrecht : Springer Netherlands, 1985. http://dx.doi.org/10.1007/978-94-009-5462-5_21.

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Puzzarini, Cristina, et Vincenzo Barone. « CHAPTER 10. Interstellar Complex Organic Molecules : A Step Toward Biomolecule Building Blocks in the Skies ». Dans Comprehensive Series in Photochemical & ; Photobiological Sciences, 195–218. Cambridge : Royal Society of Chemistry, 2021. http://dx.doi.org/10.1039/9781839164354-00195.

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« Where and How Does Life Begin ? » Dans Dust in Galaxies, 188–218. The Royal Society of Chemistry, 2019. http://dx.doi.org/10.1039/9781788015059-00188.

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The interstellar medium is rich in molecules, especially in organic molecules, and dust grains play a crucial role in much of this chemistry. In the past half-century, we've begun to realize that the interstellar medium can be not only molecular, but that interstellar chemistry is remarkably complex for what seems a quite hostile environment. Of course, the chemistry of life is much more complex than interstellar chemistry. But, wherever life begins, it must start from the kinds of molecules that are readily available in interstellar space. More than 200 different molecular species have been identified in interstellar space, and most of these are organic molecules. These molecules are caught up in the processes that make stars and planets, sticking to dust grains that combine to make meteoroids, planetesimals, asteroids, comets, and eventually planets. Objects like meteorites and comets carry with them samples of the products of interstellar chemistry that we can examine, and are rich in molecules that are necessary to make the building blocks of DNA and RNA. It's not obvious how these essential molecules can be made in an interstellar or planet-forming environment and transported safely to a planet. However, it seems likely that interstices in clusters of dust grains can provide environments that may mimic the Urey–Miller experiment in which a variety of molecules, including amino acids and sugars, were created in abundance. Perhaps clusters of dust grains could be the mechanism of forming and transporting essential molecules to planet Earth.

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« What Have We Learned About Dust in Space ? » Dans Dust in Galaxies, 219–25. The Royal Society of Chemistry, 2019. http://dx.doi.org/10.1039/9781788015059-00219.

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We summarize the variety of roles played by dust grains in the interstellar medium of the Milky Way galaxy. These range from the passive extinction of starlight from interstellar clouds to the active surface chemistry that provides the seminal molecule, molecular hydrogen, which controls all of gas-phase interstellar chemistry. The products of this gas-phase chemistry control the formation of stars and planets. Finally, dust grains have an essential role in the chemistry that forms complex organic molecules. These molecules include some species that are the building blocks of biological molecules; these building blocks are delivered to planets during and after planet formation. Evidently, dust grains may be related to the existence of life on planets. We speculate on the existence of technological civilizations elsewhere in the galaxy by considering the well-known Drake Equation. We end by noting that the Universe might be regarded as a machine for producing life, and that dust grains are an important – indeed, essential – component in that machine.

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Actes de conférences sur le sujet "Interstellar organic complex molecules iCOMS"

Cruz-Diaz, Gustavo, Susanna Widicus Weaver, Stefanie Milam, Perry Gerakines, Catherine Walker, Collette Sarver et Will Thompson. « THE SEARCH FOR COMPLEX ORGANIC MOLECULES DESORBING FROM INTERSTELLAR ICE ANALOGS : PRESENTING SubLIME2 ». Dans 2022 International Symposium on Molecular Spectroscopy. Urbana, Illinois : University of Illinois at Urbana-Champaign, 2022. http://dx.doi.org/10.15278/isms.2022.fg03.

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Wehres, Nadine, Susanna Widicus Weaver, Eric Herbst, D. Lis, Trevor Cross, Brian Hays, Jacob Laas et al. « DETECTION, IDENTIFICATION AND CORRELATION OF COMPLEX ORGANIC MOLECULES IN 32 INTERSTELLAR CLOUDS USING SUBMM OBSERVATIONS ». Dans 69th International Symposium on Molecular Spectroscopy. Urbana, Illinois : University of Illinois at Urbana-Champaign, 2014. http://dx.doi.org/10.15278/isms.2014.rf10.

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