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
    Electronic Resource
    Electronic Resource
    Crystal structure of 2,4,6-triphenylverdazyl (1973)
    Copenhagen : International Union of Crystallography (IUCr)
    Acta crystallographica 29 (1973), S. 96-102 
    Details
    ISSN: 1600-5740
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0567740873002037
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 2
    Electronic Resource
    Electronic Resource
    2,2,4,4-Tetramethyl-1,3-cyclobutanedione (1974)
    Copenhagen : International Union of Crystallography (IUCr)
    Acta crystallographica 30 (1974), S. 245-246 
    Details
    ISSN: 1600-5740
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0567740874002573
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 3
    Electronic Resource
    Electronic Resource
    The crystal structure of 2,2,4,4-tetramethyl-3-thio-l,3-cyclobutanedione (1974)
    Copenhagen : International Union of Crystallography (IUCr)
    Acta crystallographica 30 (1974), S. 1974-1978 
    Details
    ISSN: 1600-5740
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0567740874006212
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 4
    Electronic Resource
    Electronic Resource
    Optimally spaced rotational grid points (1973)
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 29 (1973), S. 408-414 
    Details
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: Optimal rotational spacing was obtained for n = 2 to 12 orientations of an object in three-dimensional space. For n = 2, 3, and 4 the minimum spacing, χ(min), was 180°, with rotation space not being completely filled. For n = 5 and 6 all spacings are equal to 151.05 and 141.06° respectively. The n = 7 case has two spacings at 134.04 and 180°. The n = 8 case has two spacings at 130.18 and 153.56°. The n = 10 case has three spacings at 128.53, 141.05 and 164.8°. The n = 12 case has two spacings at 120 and 180°. The best arrangement found for n = 9 and 11 was to remove one grid point from n = 10 and 12 respectively. The coordination about each point and the orientations of the grid difference rotation axes are given. The axes for n = 5 are directed toward the vertices of a regular dodecahedron; the axes for n= 12 are directed toward the vertices and faces of a cube. Products of two rotations of equal magnitude to give a third rotation of the same magnitude were considered and classified into conrotatory and disrotatory types. For n 〉 12 the Lattman treatment was extended to include third-order terms. Examples of Lattmanian angle grids are given and the grid spacings are compared to theoretical estimates.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0567739473001014
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 5
    Electronic Resource
    Electronic Resource
    Accelerated convergence of crystal-lattice potential sums (1971)
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 27 (1971), S. 452-455 
    Details
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: A method for increasing the rate of convergence of general crystal lattice sums of the type \sum_{j \ne k} qjqkr−njk is described. The method is applicable for n 〉 3, or for n 〉 0 if \sum_{\rm cell} qj = 0. A numerical example is given for the London dispersion energy (n = 6) of the benzene crystal. The calculation effort required to obtain the lattice sum was reduced at least tenfold.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0567739471000998
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 6
    Electronic Resource
    Electronic Resource
    Coulombic interactions in crystalline hydrocarbons (1974)
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 30 (1974), S. 71-77 
    Details
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: Coulombic intermolecular interactions in crystalline hydrocarbons were studied by means of molecular packing analysis. A C-H charge separation parameter of 0.36 e was found by analysis of nine aromatic and nine saturated hydrocarbon crystal structures. When coulombic point charges were included in the non-bonded potential model it was found that the geometric-mean combining law held for C. . .H repulsions. The calculated coulombic energy of the hydrocarbons studied ranged from a negligible amount for n-hexane to a maximum contribution of 29% of the total lattice energy for crystalline benzene.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0567739474010771
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 7
    Electronic Resource
    Electronic Resource
    Direct calculations of crystalline thermal expansion and molecular reorientation from nonbonded interatomic potential anharmonicity and thermal amplitudes (1972)
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 28 (1972), S. 84-88 
    Details
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: Non-bonded interatomic potential functions were altered to allow for the effects of vibration and anharmonicity by relating the mean displacement to the mean-square vibrational amplitude through the anharmonicity constant, K. Vibrational amplitudes were calculated in the harmonic approximation. The repulsive coefficient, B, of the potential was increased sufficiently to cause the minimum of the potential to shift by the amount of the displacement. The apparent lattice energy was then minimized in the usual manner. The method was checked against experiment by calculation of the lattice constants of noble gases at several temperatures, and of anthracene at two temperatures. The method differs from usual calculations of the Grüneisen type in that calculation of molecular-orientation change with temperature is possible. The anthracene molecular orientation was calculated at 95 and 290°K.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0567739472000178
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 8
    Electronic Resource
    Electronic Resource
    Molecular packing analysis (1972)
    [S.l.] : International Union of Crystallography (IUCr)
    Acta crystallographica 28 (1972), S. 629-635 
    Details
    ISSN: 1600-5724
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Notes: A general method of molecular packing analysis based on the minimization of the crystal lattice energy is described. The lattice energy was approximated by a pairwise sum over nonbonded atoms in different molecules, using (exp–6–1) potential functions. Increased speed of calculation of the lattice sums was achieved by a convergence acceleration technique. The variables considered were six rigid body rotations and translations for each molecule in the asymmetric unit, and the six lattice constants. Molecular flexibility was allowed in the form of internal rotations about bonds (subrotations). In this event additional subrotation potentials of the cos2 ψ type could be used to allow for conjugation energy, and the subrotation angles were additional variables. An optional thermal correction, based on the mean square thermal amplitudes and the potential anharmonicities, was applied to calculate the anisotropic thermal expansion. Nonbonded potential parameters, including conjugation energies, were found by fitting them to observed crystal structures.
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0567739472001561
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 9
    Electronic Resource
    Electronic Resource
    The crystal structure of 2,2,4,4-tetramethyl-l,3-cyclobutanedithione (1973)
    Copenhagen : International Union of Crystallography (IUCr)
    Acta crystallographica 29 (1973), S. 1648-1653 
    Details
    ISSN: 1600-5740
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0567740873005194
    Location Call Number Expected Availability
    BibTip Others were also interested in ...
    Paper (German National Licenses)
    Fulltext
  • 10
    Electronic Resource
    Electronic Resource
    The crystal structure of 2-isopropylidene-1,1,7,7,9,9-hexamethyl-3,5,10,11-tetrathiadispiro[3,1,3,2]undecane-8-thione (1973)
    Copenhagen : International Union of Crystallography (IUCr)
    Acta crystallographica 29 (1973), S. 2128-2133 
    Details
    ISSN: 1600-5740
    Source: Crystallography Journals Online : IUCR Backfile Archive 1948-2001
    Topics: Chemistry and Pharmacology , Geosciences , Physics
    Type of Medium: Electronic Resource
    URL: http://dx.doi.org/10.1107/S0567740873006229
    Location Call Number Expected 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...