Library

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
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    The @journal of physical chemistry 〈Washington, DC〉 93 (1989), S. 1745-1752 
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 2
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    The @journal of physical chemistry 〈Washington, DC〉 92 (1988), S. 294-299 
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 3
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    The @journal of physical chemistry 〈Washington, DC〉 94 (1990), S. 5449-5454 
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 4
    Electronic Resource
    Electronic Resource
    s.l. : American Chemical Society
    The @journal of physical chemistry 〈Washington, DC〉 90 (1986), S. 5669-5671 
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 5
    Electronic Resource
    Electronic Resource
    Springer
    Structural chemistry 1 (1990), S. 171-178 
    ISSN: 1572-9001
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract The structures of B2H5·, B2H5CO·, and B2H5N2· radicals are investigated using the 6–31G* basis set. Both double H-bridged and single H-bridged isomers are found to be local minima on the potential energy surface. The effects of electron correlation are taken into account using single point MP4/6–31G* calculations and, for the diboryl radicals, complete MP3/6–31G* optimizations. In all cases the single H-bridged isomers are found to be more stable than the corresponding double H-bridged isomers. The transition state for the double H-bridged to single H-bridged B2H5· isomerization reaction is calculated to be 2.54 kcal mol−1 above the double H-bridged radical at the MP4SDTQ/6-31G*//UHF/ 6–31 G* level when corrected for zero point energy. Barrier tunneling increased the reaction rate by a factor of 2.5–3.0, strongly suggesting the system is fluxional at this temperature. The addition of CO and N2 to the diboryl radicals leads to relocation of the unpaired electron and rehybridization of the C and N atoms adjacent to the boron atoms. The isomers of B2H5CO· and B2H5N2· are different and should be distinguishable experimentally. While the CO moiety is bound to the diboryl radicals isomers by over 19 kcal mol−1, no binding energy is evident for N2.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 6
    ISSN: 1573-9171
    Keywords: dinitramines ; quantum chemistry ; molecular structures ; force fields ; vibrational spectra
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract Ab initio geometries and vibrational spectra have been calculated for the amine structures of dinitramine and methyldinitramine, HN(NO2)2 and CH3N(NO2)2. It is shown at the RHF and MP2 levels with the use of the 6-31G* and 6-31G** basis sets that these molecules have different symmetries in their equilibrium states,C sandC 1 respectively. The quantum chemical RHF/6-31G* force fields were scaled with the set of transferable factors previously obtained by the authors to assign the available experimental vibrational bands and predict the positions of bands for the unmeasured spectral regions. Some common patterns of the geometrical parameters, vibrational spectra, and force fields of the simplest nitramines are discussed.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 7
    Electronic Resource
    Electronic Resource
    New York, NY : Wiley-Blackwell
    International Journal of Quantum Chemistry 15 (1979), S. 423-443 
    ISSN: 0020-7608
    Keywords: Computational Chemistry and Molecular Modeling ; Atomic, Molecular and Optical Physics
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology
    Notes: The expectation energy values EK, Vee, Vnn, Ven, and ET have been calculated for H2 and the C1, C2, and C3 hydrocarbons using a (9,5) basis set and the experimental geometries. Treating the theoretical reaction heat, ΔET, as the resultant of the nuclear repulsion term, ΔVnn, and the net electron energy term, ΔEelec = ΔEK + ΔVee + ΔVen, the contribution of inner and outer shell electron energies to ΔEelec, and hence to ΔET, has been calculated for a large number of hydrocarbon reactions by evaluating the Coulson-Neilson energies ηi, where Σηi = Eelec. For the vast majority of reactions, 67/84, the change in inner shell electron energy, (Σηi)inner, accounts for more than 10% of ΔEelec, in many cases being as high as 20-35%. Furthermore, in addition to these cases in which the change in inner shell electron energy serves to augment (significantly) the change in outer shell electron energy, there are other cases in which the change in inner shell electron energy either exceeds in magnitude the change in outer shell energy, or is even opposite in sign, indicative of inner and outer shell electrons acting contrariwise. Inner shell electron energies contribute to the reaction heats because they are structure dependent, like the more familiar orbital energies ε, but the dependence is of a different kind.
    Additional Material: 2 Ill.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
  • 8
    Electronic Resource
    Electronic Resource
    New York, NY [u.a.] : Wiley-Blackwell
    Journal of Computational Chemistry 11 (1990), S. 623-628 
    ISSN: 0192-8651
    Keywords: Computational Chemistry and Molecular Modeling ; Biochemistry
    Source: Wiley InterScience Backfile Collection 1832-2000
    Topics: Chemistry and Pharmacology , Computer Science
    Notes: The completely optimized structure and harmonic force field of s-trans-buta-1,3-diene are reported at the MP2/6-31G and MP2/6-31G* levels of computation. Sets of empirical scale factors for the calculated force fields are derived and compared with the corresponding values computed at the RHF/4-31G and RHF/6-31G levels. Changes in the scale factors for this series of force fields are discussed. The vibrational frequencies are also reported for thirteen isotopomers of s-trans-buta-1,3-diene using the MP2/6-31G* force field. Some characteristics of the gauche and cis forms of buta-1,3-diene are also given.
    Additional Material: 5 Tab.
    Type of Medium: Electronic Resource
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...