ALBERT

All Library Books, journals and Electronic Records Telegrafenberg

X
feed icon rss

Your email was sent successfully. Check your inbox.

An error occurred while sending the email. Please try again.

Proceed reservation?

Export
  • 1
    facet.materialart.
    Unknown
    The C4H7+ cation. A theoretical investigation (1988)
    In:  Other Sources
    Details
    Publication Date: 2011-08-24
    Description: The potential energy surface of the C4H7+ cation has been investigated with ab initio quantum chemical theory. Extended basis set calculations, including electronic correlation, show that cyclobutyl and cyclopropylcarbinyl cation are equally stable isomers. The saddle point connecting these isomers lies 0.6 kcal/mol above the minima. The global C4H7+ minimum corresponds to the 1-methylallyl cation, which is 9.0 kcal/mol more stable than the cyclobutyl and the cyclopropylcarbinyl cation and 9.5 kcal/mol below the 2-methylallyl cation. These results are in excellent agreement with experimental data.
    Keywords: Exobiology
    Type: Journal of the American Chemical Society (ISSN 0002-7863); Volume 110; 22; 7325-8
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 2
    facet.materialart.
    Unknown
    Ab initio study of C + H3+ reactions (1991)
    In:  Other Sources
    Details
    Publication Date: 2011-08-24
    Description: The reaction C + H3+ --〉 CH(+) + H2 is frequently used in models of dense interstellar cloud chemistry with the assumption that it is fast, i.e. there are no potential energy barriers inhibiting it. Ab initio molecular orbital study of the triplet CH3+ potential energy surface (triplet because the reactant carbon atom is a ground state triplet) supports this hypothesis. The reaction product is 3 pi CH+; the reaction is to exothermic even though the product is not in its electronic ground state. No path has been found on the potential energy surface for C + H3+ --〉 CH2(+) + H reaction.
    Keywords: Exobiology
    Type: Chemical physics letters (ISSN 0009-2614); Volume 179; 1-2; 165-8
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 3
    facet.materialart.
    Unknown
    Structure of the 2-norbornyl cation (1989)
    In:  Other Sources
    Details
    Publication Date: 2011-08-24
    Description: No abstract available
    Keywords: Exobiology
    Type: Journal of the American Chemical Society (ISSN 0002-7863); Volume 111; 1527-8
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 4
    facet.materialart.
    Unknown
    Theoretical IR spectra of ionized naphthalene (1992)
    In:  Other Sources
    Details
    Publication Date: 2019-07-13
    Description: We report the results of a theoretical study of the effect of ionization on the IR spectrum of naphthalene, using ab initio molecular orbital theory. For that purpose we determined the structures, band frequencies, and intensities of neutral and positively ionized naphthalene. The calculated frequencies and intensities allowed an assignment of the most important bands appearing in the newly reported experimental spectrum of the positive ion. Agreement with the experimental spectrum is satisfactory enough to take into consideration the unexpected and important result that ionization significantly affects the intensities of most vibrations. A possible consequence on the interpretation of the IR interstellar emission, generally supposed to originate from polycyclic aromatic hydrocarbons (PAHs), is briefly presented.
    Keywords: Exobiology
    Type: The Journal of physical chemistry (ISSN 0022-3654); 96; 20; 7882-6
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 5
    facet.materialart.
    Unknown
    Experimental and theoretical IR spectra of the 2-norbornyl cation (1990)
    In:  Other Sources
    Details
    Publication Date: 2019-07-13
    Description: No abstract available
    Keywords: Exobiology
    Type: Angewandte Chemie (International ed. in English) (ISSN 0570-0833); 29; 2; 183-5
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 6
    facet.materialart.
    Unknown
    Ab initio determination of the proton affinities of small neutral and anionic molecules (1986)
    In:  Other Sources
    Details
    Publication Date: 2019-07-13
    Description: The proton affinity of a molecule in the gas phase is a fundamental measure of its basicity and is the factor controlling the course of many ion-molecule reactions. In this article, ab initio molecular orbital theory at the MP4/6-311 ++ G(3df, 3pd) level of theory is demonstrated to predict proton affinities (PA's) for small neutral and anionic bases to within 2 kcal mol-1. Furthermore, the errors are random, indicating that there are likely no systematic errors in either the experimental or theoretical PA's. Also, this level of theory is used to calibrate less sophisticated theoretical models which are suitable for larger molecules; the MP4/6-311 ++ G(2d, 2p) and MP2/6-311 ++ G(d, p) theoretical models should be particularly useful. A procedure for predicting the vibrational frequencies for anion is proposed and applied to CH3-, NH2-, OH-, and CN-.
    Keywords: Exobiology
    Type: Journal of computational chemistry (ISSN 0192-8651); 7; 3; 321-33
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
  • 7
    facet.materialart.
    Unknown
    A priori predictions of the rotational constants for HC13N, HC15N, C5O (1989)
    In:  Other Sources
    Details
    Publication Date: 2019-07-13
    Description: Ab initio molecular orbital theory is used to estimate the rotational constant for several carbon-chain molecules that are candidates for discovery in interstellar space. These estimated rotational constants can be used in laboratory or astronomical searches for the molecules. The rotational constant for HC13N is estimated to be 0.1073 +/- 0.0002 GHz and its dipole moment 5.4 D. The rotational constant for HC15N is estimated to be 0.0724 GHz, with a somewhat larger uncertainty. The rotational constant of C5O is estimated to be 1.360 +/- 2% GHz and its dipole moment 4.4. D.
    Keywords: Exobiology
    Type: Chemical physics letters (ISSN 0009-2614); 158; 6; 540-4
    Format: text
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    NASA TECHNICAL REPORTS
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...