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Thierry Chiavassa - One of the best experts on this subject based on the ideXlab platform.
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Aminoacetonitrile characterization in astrophysical-like conditions
Astronomy and Astrophysics, 2012Co-Authors: Fabien Borget, Fabrice Duvernay, Patrice Theulé, Grégoire Danger, Miroslav Chomat, V. Vinogradoff, Thierry ChiavassaAbstract:Context. Aminoacetonitrile (AAN) has been detected in 2008 in the hot core SgrB2. This molecule is of particular interest because it is a central molecule in the Strecker synthesis of amino acids. This molecule can be formed from methanimine (CH2NH), ammonia (NH3) and hydrogen cyanide (HCN) in astrophysical icy conditions. Nevertheless, few studies exist about its infrared (IR) identification or its astrophysical characterization. Aims. We present in this study a characterization of the pure solid AAN and when it is diluted in water to study the influence of H2O on the main IR features of AAN. The reactivity with CO2 and its photoreactivity are also studied and the main products were characterized. Methods. Fourier transformed infrared (FTIR) spectroscopy of AAN molecular ice was performed in the 10–300 K temperature range. We used temperature-programmed desorption coupled with mass spectrometry detection techniques to evaluate the desorption energy value. The influence of water was studied by quantitative FTIR spectroscopy and the main reaction and photochemical products were identified by FTIR spectroscopy. Results. We determined that in our experimental conditions, the IR limit of AAN detection in the water ice is about 1 × 10 16 molecule cm −2 , which means that the AAN detection is almost impossible within the icy mantle of interstellar grains. The desorption energy of pure solid AAN is of 63.7 kJ mol −1 with ν0 to 10 28 molecule cm −2 s −1 , which implies that the presence of this molecule in the gas phase is only possible in hot cores. The glycine (Gly) formation from the AAN through the last step of the Strecker synthesis seems to be impossible in astrophysical-like conditions. Furthermore, AAN is photoresistant to vacuum ultra-violet radiation, which emphasizes the fact that AAN can be considered as a Gly reservoir molecule.
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experimental investigation of Aminoacetonitrile formation through the strecker synthesis in astrophysical like conditions reactivity of methanimine ch2nh ammonia nh3 and hydrogen cyanide hcn
Astronomy and Astrophysics, 2011Co-Authors: Grégoire Danger, Fabien Borget, Le Sergeant L Dhendecourt, Fabrice Duvernay, Patrice Theulé, Jean-claude Guillemin, Miroslav Chomat, Thierry ChiavassaAbstract:Astronomy & Astrophysics Experimental investigation of Aminoacetonitrile formation through the Strecker synthesis in astrophysical-like conditions: reactivity of methanimine (CH 2 NH), ammonia (NH 3), and hydrogen cyanide (HCN) ABSTRACT Context. Studing chemical reactivity in astrophysical environments is an important means for improving our understanding of the origin of the organic matter in molecular clouds, in protoplanetary disks, and possibly, as a final destination, in our solar system. Laboratory simulations of the reactivity of ice analogs provide important insight into the reactivity in these environments. Here, we use these experimental simulations to investigate the Strecker synthesis leading to the formation of Aminoacetonitrile in astrophysical-like conditions. The Aminoacetonitrile is an interesting compound because it was detected in SgrB2, hence could be a precursor of the smallest amino acid molecule, glycine, in astrophysical environments. Aims. We present the first experimental investigation of the formation of Aminoacetonitrile NH 2 CH 2 CN from the thermal processing of ices including methanimine (CH 2 NH), ammonia (NH 3), and hydrogen cyanide (HCN) in interstellar-like conditions without VUV photons or particules. Methods. We use Fourier Transform InfraRed (FTIR) spectroscopy to monitor the ice evolution during its warming. Infrared spec-troscopy and mass spectroscopy are then used to identify the Aminoacetonitrile formation. Results. We demonstrate that methanimine can react with − CN during the warming of ice analogs containing at 20 K methanimine, ammonia, and [NH + 4 − CN] salt. During the ice warming, this reaction leads to the formation of poly(methylene-imine) polymers. The polymer length depend on the initial ratio of mass contained in methanimine to that in the [NH + 4 − CN] salt. In a methanimine excess, long polymers are formed. As the methanimine is progressively diluted in the [NH + 4 − CN] salt, the polymer length decreases until the Aminoacetonitrile formation at 135 K. Therefore, these results demonstrate that Aminoacetonitrile can be formed through the second step of the Strecker synthesis in astrophysical-like conditions.
Grégoire Danger - One of the best experts on this subject based on the ideXlab platform.
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Aminoacetonitrile characterization in astrophysical-like conditions
Astronomy and Astrophysics, 2012Co-Authors: Fabien Borget, Fabrice Duvernay, Patrice Theulé, Grégoire Danger, Miroslav Chomat, V. Vinogradoff, Thierry ChiavassaAbstract:Context. Aminoacetonitrile (AAN) has been detected in 2008 in the hot core SgrB2. This molecule is of particular interest because it is a central molecule in the Strecker synthesis of amino acids. This molecule can be formed from methanimine (CH2NH), ammonia (NH3) and hydrogen cyanide (HCN) in astrophysical icy conditions. Nevertheless, few studies exist about its infrared (IR) identification or its astrophysical characterization. Aims. We present in this study a characterization of the pure solid AAN and when it is diluted in water to study the influence of H2O on the main IR features of AAN. The reactivity with CO2 and its photoreactivity are also studied and the main products were characterized. Methods. Fourier transformed infrared (FTIR) spectroscopy of AAN molecular ice was performed in the 10–300 K temperature range. We used temperature-programmed desorption coupled with mass spectrometry detection techniques to evaluate the desorption energy value. The influence of water was studied by quantitative FTIR spectroscopy and the main reaction and photochemical products were identified by FTIR spectroscopy. Results. We determined that in our experimental conditions, the IR limit of AAN detection in the water ice is about 1 × 10 16 molecule cm −2 , which means that the AAN detection is almost impossible within the icy mantle of interstellar grains. The desorption energy of pure solid AAN is of 63.7 kJ mol −1 with ν0 to 10 28 molecule cm −2 s −1 , which implies that the presence of this molecule in the gas phase is only possible in hot cores. The glycine (Gly) formation from the AAN through the last step of the Strecker synthesis seems to be impossible in astrophysical-like conditions. Furthermore, AAN is photoresistant to vacuum ultra-violet radiation, which emphasizes the fact that AAN can be considered as a Gly reservoir molecule.
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experimental investigation of Aminoacetonitrile formation through the strecker synthesis in astrophysical like conditions reactivity of methanimine ch2nh ammonia nh3 and hydrogen cyanide hcn
Astronomy and Astrophysics, 2011Co-Authors: Grégoire Danger, Fabien Borget, Le Sergeant L Dhendecourt, Fabrice Duvernay, Patrice Theulé, Jean-claude Guillemin, Miroslav Chomat, Thierry ChiavassaAbstract:Astronomy & Astrophysics Experimental investigation of Aminoacetonitrile formation through the Strecker synthesis in astrophysical-like conditions: reactivity of methanimine (CH 2 NH), ammonia (NH 3), and hydrogen cyanide (HCN) ABSTRACT Context. Studing chemical reactivity in astrophysical environments is an important means for improving our understanding of the origin of the organic matter in molecular clouds, in protoplanetary disks, and possibly, as a final destination, in our solar system. Laboratory simulations of the reactivity of ice analogs provide important insight into the reactivity in these environments. Here, we use these experimental simulations to investigate the Strecker synthesis leading to the formation of Aminoacetonitrile in astrophysical-like conditions. The Aminoacetonitrile is an interesting compound because it was detected in SgrB2, hence could be a precursor of the smallest amino acid molecule, glycine, in astrophysical environments. Aims. We present the first experimental investigation of the formation of Aminoacetonitrile NH 2 CH 2 CN from the thermal processing of ices including methanimine (CH 2 NH), ammonia (NH 3), and hydrogen cyanide (HCN) in interstellar-like conditions without VUV photons or particules. Methods. We use Fourier Transform InfraRed (FTIR) spectroscopy to monitor the ice evolution during its warming. Infrared spec-troscopy and mass spectroscopy are then used to identify the Aminoacetonitrile formation. Results. We demonstrate that methanimine can react with − CN during the warming of ice analogs containing at 20 K methanimine, ammonia, and [NH + 4 − CN] salt. During the ice warming, this reaction leads to the formation of poly(methylene-imine) polymers. The polymer length depend on the initial ratio of mass contained in methanimine to that in the [NH + 4 − CN] salt. In a methanimine excess, long polymers are formed. As the methanimine is progressively diluted in the [NH + 4 − CN] salt, the polymer length decreases until the Aminoacetonitrile formation at 135 K. Therefore, these results demonstrate that Aminoacetonitrile can be formed through the second step of the Strecker synthesis in astrophysical-like conditions.
Jean-claude Guillemin - One of the best experts on this subject based on the ideXlab platform.
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experimental investigation of Aminoacetonitrile formation through the strecker synthesis in astrophysical like conditions reactivity of methanimine ch2nh ammonia nh3 and hydrogen cyanide hcn
Astronomy and Astrophysics, 2011Co-Authors: Grégoire Danger, Fabien Borget, Le Sergeant L Dhendecourt, Fabrice Duvernay, Patrice Theulé, Jean-claude Guillemin, Miroslav Chomat, Thierry ChiavassaAbstract:Astronomy & Astrophysics Experimental investigation of Aminoacetonitrile formation through the Strecker synthesis in astrophysical-like conditions: reactivity of methanimine (CH 2 NH), ammonia (NH 3), and hydrogen cyanide (HCN) ABSTRACT Context. Studing chemical reactivity in astrophysical environments is an important means for improving our understanding of the origin of the organic matter in molecular clouds, in protoplanetary disks, and possibly, as a final destination, in our solar system. Laboratory simulations of the reactivity of ice analogs provide important insight into the reactivity in these environments. Here, we use these experimental simulations to investigate the Strecker synthesis leading to the formation of Aminoacetonitrile in astrophysical-like conditions. The Aminoacetonitrile is an interesting compound because it was detected in SgrB2, hence could be a precursor of the smallest amino acid molecule, glycine, in astrophysical environments. Aims. We present the first experimental investigation of the formation of Aminoacetonitrile NH 2 CH 2 CN from the thermal processing of ices including methanimine (CH 2 NH), ammonia (NH 3), and hydrogen cyanide (HCN) in interstellar-like conditions without VUV photons or particules. Methods. We use Fourier Transform InfraRed (FTIR) spectroscopy to monitor the ice evolution during its warming. Infrared spec-troscopy and mass spectroscopy are then used to identify the Aminoacetonitrile formation. Results. We demonstrate that methanimine can react with − CN during the warming of ice analogs containing at 20 K methanimine, ammonia, and [NH + 4 − CN] salt. During the ice warming, this reaction leads to the formation of poly(methylene-imine) polymers. The polymer length depend on the initial ratio of mass contained in methanimine to that in the [NH + 4 − CN] salt. In a methanimine excess, long polymers are formed. As the methanimine is progressively diluted in the [NH + 4 − CN] salt, the polymer length decreases until the Aminoacetonitrile formation at 135 K. Therefore, these results demonstrate that Aminoacetonitrile can be formed through the second step of the Strecker synthesis in astrophysical-like conditions.
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Ni+ reactions with Aminoacetonitrile, a potential prebiological precursor of glycine
Journal of Mass Spectrometry, 2008Co-Authors: Al Mokhtar Lamsabhi, Jean-claude Guillemin, Manuel Yáñez, Violette Haldys, Jeanine Tortajada, Jean-yves SalpinAbstract:The gas‐phase reactions between Ni+ (2D5/2) and Aminoacetonitrile, a molecule of prebiological interest as possible precursor of glycine, have been investigated by means of mass spectrometry techniques. The mass‐analyzed ion kinetic energy (MIKE) spectrum reveals that the adduct ions [NC-CH2-NH2, Ni+] spontaneously decompose by loosing HCN, H2, and H2CNH, the loss of hydrogen cyanide being clearly dominant. The structures and bonding characteristics of the Aminoacetonitrile–Ni+ complexes as well as the different stationary points of the corresponding potential energy surface (PES) have been theoretically studied by density functional theory (DFT) calculations carried out at B3LYP/6‐311G(d,p) level. A cyclic intermediate, in which Ni+ is bisligated to the cyano and the amino group, plays an important role in the unimolecular reactivity of these ions, because it is the precursor for the observed losses of HCN and H2CNH. In all mechanisms associated with the loss of H2, the metal acts as hydrogen carrier favoring the formation of the H2 molecule. The estimated bond dissociation energy of Aminoacetonitrile–Ni+ complexes (291 kJ mol−1) is larger than those measured for other nitrogen bases such as pyridine or pyrimidine and only slightly smaller than that of adenine.
Le Sergeant L Dhendecourt - One of the best experts on this subject based on the ideXlab platform.
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experimental investigation of Aminoacetonitrile formation through the strecker synthesis in astrophysical like conditions reactivity of methanimine ch2nh ammonia nh3 and hydrogen cyanide hcn
Astronomy and Astrophysics, 2011Co-Authors: Grégoire Danger, Fabien Borget, Le Sergeant L Dhendecourt, Fabrice Duvernay, Patrice Theulé, Jean-claude Guillemin, Miroslav Chomat, Thierry ChiavassaAbstract:Astronomy & Astrophysics Experimental investigation of Aminoacetonitrile formation through the Strecker synthesis in astrophysical-like conditions: reactivity of methanimine (CH 2 NH), ammonia (NH 3), and hydrogen cyanide (HCN) ABSTRACT Context. Studing chemical reactivity in astrophysical environments is an important means for improving our understanding of the origin of the organic matter in molecular clouds, in protoplanetary disks, and possibly, as a final destination, in our solar system. Laboratory simulations of the reactivity of ice analogs provide important insight into the reactivity in these environments. Here, we use these experimental simulations to investigate the Strecker synthesis leading to the formation of Aminoacetonitrile in astrophysical-like conditions. The Aminoacetonitrile is an interesting compound because it was detected in SgrB2, hence could be a precursor of the smallest amino acid molecule, glycine, in astrophysical environments. Aims. We present the first experimental investigation of the formation of Aminoacetonitrile NH 2 CH 2 CN from the thermal processing of ices including methanimine (CH 2 NH), ammonia (NH 3), and hydrogen cyanide (HCN) in interstellar-like conditions without VUV photons or particules. Methods. We use Fourier Transform InfraRed (FTIR) spectroscopy to monitor the ice evolution during its warming. Infrared spec-troscopy and mass spectroscopy are then used to identify the Aminoacetonitrile formation. Results. We demonstrate that methanimine can react with − CN during the warming of ice analogs containing at 20 K methanimine, ammonia, and [NH + 4 − CN] salt. During the ice warming, this reaction leads to the formation of poly(methylene-imine) polymers. The polymer length depend on the initial ratio of mass contained in methanimine to that in the [NH + 4 − CN] salt. In a methanimine excess, long polymers are formed. As the methanimine is progressively diluted in the [NH + 4 − CN] salt, the polymer length decreases until the Aminoacetonitrile formation at 135 K. Therefore, these results demonstrate that Aminoacetonitrile can be formed through the second step of the Strecker synthesis in astrophysical-like conditions.
Fabien Borget - One of the best experts on this subject based on the ideXlab platform.
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Aminoacetonitrile characterization in astrophysical-like conditions
Astronomy and Astrophysics, 2012Co-Authors: Fabien Borget, Fabrice Duvernay, Patrice Theulé, Grégoire Danger, Miroslav Chomat, V. Vinogradoff, Thierry ChiavassaAbstract:Context. Aminoacetonitrile (AAN) has been detected in 2008 in the hot core SgrB2. This molecule is of particular interest because it is a central molecule in the Strecker synthesis of amino acids. This molecule can be formed from methanimine (CH2NH), ammonia (NH3) and hydrogen cyanide (HCN) in astrophysical icy conditions. Nevertheless, few studies exist about its infrared (IR) identification or its astrophysical characterization. Aims. We present in this study a characterization of the pure solid AAN and when it is diluted in water to study the influence of H2O on the main IR features of AAN. The reactivity with CO2 and its photoreactivity are also studied and the main products were characterized. Methods. Fourier transformed infrared (FTIR) spectroscopy of AAN molecular ice was performed in the 10–300 K temperature range. We used temperature-programmed desorption coupled with mass spectrometry detection techniques to evaluate the desorption energy value. The influence of water was studied by quantitative FTIR spectroscopy and the main reaction and photochemical products were identified by FTIR spectroscopy. Results. We determined that in our experimental conditions, the IR limit of AAN detection in the water ice is about 1 × 10 16 molecule cm −2 , which means that the AAN detection is almost impossible within the icy mantle of interstellar grains. The desorption energy of pure solid AAN is of 63.7 kJ mol −1 with ν0 to 10 28 molecule cm −2 s −1 , which implies that the presence of this molecule in the gas phase is only possible in hot cores. The glycine (Gly) formation from the AAN through the last step of the Strecker synthesis seems to be impossible in astrophysical-like conditions. Furthermore, AAN is photoresistant to vacuum ultra-violet radiation, which emphasizes the fact that AAN can be considered as a Gly reservoir molecule.
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experimental investigation of Aminoacetonitrile formation through the strecker synthesis in astrophysical like conditions reactivity of methanimine ch2nh ammonia nh3 and hydrogen cyanide hcn
Astronomy and Astrophysics, 2011Co-Authors: Grégoire Danger, Fabien Borget, Le Sergeant L Dhendecourt, Fabrice Duvernay, Patrice Theulé, Jean-claude Guillemin, Miroslav Chomat, Thierry ChiavassaAbstract:Astronomy & Astrophysics Experimental investigation of Aminoacetonitrile formation through the Strecker synthesis in astrophysical-like conditions: reactivity of methanimine (CH 2 NH), ammonia (NH 3), and hydrogen cyanide (HCN) ABSTRACT Context. Studing chemical reactivity in astrophysical environments is an important means for improving our understanding of the origin of the organic matter in molecular clouds, in protoplanetary disks, and possibly, as a final destination, in our solar system. Laboratory simulations of the reactivity of ice analogs provide important insight into the reactivity in these environments. Here, we use these experimental simulations to investigate the Strecker synthesis leading to the formation of Aminoacetonitrile in astrophysical-like conditions. The Aminoacetonitrile is an interesting compound because it was detected in SgrB2, hence could be a precursor of the smallest amino acid molecule, glycine, in astrophysical environments. Aims. We present the first experimental investigation of the formation of Aminoacetonitrile NH 2 CH 2 CN from the thermal processing of ices including methanimine (CH 2 NH), ammonia (NH 3), and hydrogen cyanide (HCN) in interstellar-like conditions without VUV photons or particules. Methods. We use Fourier Transform InfraRed (FTIR) spectroscopy to monitor the ice evolution during its warming. Infrared spec-troscopy and mass spectroscopy are then used to identify the Aminoacetonitrile formation. Results. We demonstrate that methanimine can react with − CN during the warming of ice analogs containing at 20 K methanimine, ammonia, and [NH + 4 − CN] salt. During the ice warming, this reaction leads to the formation of poly(methylene-imine) polymers. The polymer length depend on the initial ratio of mass contained in methanimine to that in the [NH + 4 − CN] salt. In a methanimine excess, long polymers are formed. As the methanimine is progressively diluted in the [NH + 4 − CN] salt, the polymer length decreases until the Aminoacetonitrile formation at 135 K. Therefore, these results demonstrate that Aminoacetonitrile can be formed through the second step of the Strecker synthesis in astrophysical-like conditions.