Library

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
    Electronic Resource
    Electronic Resource
    Effect of solvation on the shapes, sizes, and anisotropies of polyatomic anions via molecular electrostatic potential topography: An ab initio self-consistent reaction field approach (1994)
    College Park, Md. : American Institute of Physics (AIP)
    The Journal of Chemical Physics 100 (1994), S. 6718-6726 
    Details
    ISSN: 1089-7690
    Source: AIP Digital Archive
    Topics: Physics , Chemistry and Pharmacology
    Notes: The effect of solvation, as studied by the self-consistent reaction field procedure, on the shapes, sizes, and anisotropies of eight small prototypical anions (OH−, NH−2, CH−3, CN−, SH−, N−3, NO−2, and NO−3) has been studied at the ab initio 6–31++G(d) level. Both the general molecular electrostatic potential distribution and the molecular electrostatic potential topography have been used for examining the effect of solvation. The results demonstrate both the complexity and specificity of the hydration effect on the solute charge distribution. It is observed that in general anions tend to shrink upon solvation. The molecular electrostatic potential, in general, becomes more negative and the electron density is increased upon solvation. The effect of the solvation on the chemical reactivity and anisotropy of the anions in aqueous environment is discussed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1063/1.467032
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    SCRF calculation of the effect of water on the topology of the molecular electrostatic potential (1993)
    s.l. : American Chemical Society
    The @journal of physical chemistry 〈Washington, DC〉 97 (1993), S. 9380-9384 
    Details
    Source: ACS Legacy Archives
    Topics: Chemistry and Pharmacology , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1021/j100139a021
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    Theoretical studies on the structure of M+BF−4 ion pairs M = Li+, NH+4: the role of electrostatics and electron correlation (1998)
    Springer
    Theoretical chemistry accounts 99 (1998), S. 151-157 
    Details
    ISSN: 1432-2234
    Keywords: Key words: Molecular electrostatic potential ; Ab initio calculations
    Source: Springer Online Journal Archives 1860-2000
    Topics: Chemistry and Pharmacology
    Notes: Abstract. A systematic investigation of the M+BF4 − (M = Li or NH4) ion-pair conformers has been carried out using an electrostatic docking model based on the molecular electrostatic potential topography of the free anion. This method provides a guideline for the subsequent ab initio molecular orbital calculations at the Hartree-Fock (HF) and second-order Møller-Plesset perturbation theory (MP2) levels. It has been demonstrated that the model presented here yields more than 75% of the HF interaction energy when Li+ is the cation involved and more than 90% for the case of NH4 +. Inclusion of MP2 correlation in the HF-optimized geometries leads to stationary point geometries with different numbers of imaginary frequencies and in some places where the energies of two adjacent conformers are very close, the energy rank order is altered. The HF lowest-energy minima for the Li+BF4 − and NH4 +BF4 − show a bidentate and tridentate coordinating cation, respectively, whereas at the MP2 level, this ordering is reversed.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/s002140050317
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Some aspects of parallelization of two-electron integrals in molecular orbital programs (1991)
    Springer
    The European physical journal 18 (1991), S. 357-363 
    Details
    ISSN: 1434-6079
    Keywords: 31.15.+q ; 31.20.Ej
    Source: Springer Online Journal Archives 1860-2000
    Topics: Physics
    Notes: Abstract Evaluation of two-electron integrals forms a substantial part of the CPU time for any ab initio molecular orbital program. This part of the package, “MICROMOL”, is parallelized. However, this parallelization leads to only sublinear speedups (typically 3 on a 4-node machine). In view of these results, the task of development of an efficient program for two-electron integrals suitable for the parallel environment has been taken up. The program is written in FORTRAN considering specific symmetry features and application of rigorous bounds. This program is further parallelized with a good load balancing strategy. The molecules used as the test cases are: trans-butadiene, benzene, nitrobenzene, naphtalene and cytosine, with 3G and 4–31G basis sets. The results indicate that the parallel version of this program gives a typical speedup of 3.6 for a 3G basis set and approximately 3.4 for a 4–31G basis set for all the molecules tested. The sequential version of this program is ∼1.2 times faster than the sequential version of MICROMOL, whereas the parallel version is ∼1.4 times faster than the parallelized MICROMOL.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1007/BF01426598
    Library Location Call Number Volume/Issue/Year Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
Close ⊗
This website uses cookies and the analysis tool Matomo. More information can be found here...