Full-text resources of PSJD and other databases are now available in the new Library of Science.
Visit https://bibliotekanauki.pl
Preferences help
enabled [disable] Abstract
Number of results

Results found: 4

Number of results on page
first rewind previous Page / 1 next fast forward last

Search results

help Sort By:

help Limit search:
first rewind previous Page / 1 next fast forward last
1
Content available remote

Polybenzene multitori

100%
Open Chemistry
|
2012
|
vol. 10
|
issue 6
1779-1785
EN
Polybenzene unit BT_48 can dimerize either by identification of 8-membered rings to provide a diamond-like fcc net or by identifying the opening 12-membered rings to form intercalated dendrimer-dimers which can further grow and rather quickly superimpose over the diamond-like network. The third hypothetical moiety we consider here is an eclipsed isomer, that can form multitori as negatively curved structures of various complexity. Multitori can evolve spherically or show a linear periodicity, as in rods. The polybenzene (“armchair”) multitori BTA are compared to the (“zig-zag”) BTZ ones, proposed earlier by us. A graph-theoretical study related the structure of multitori to the genus of their embedding surface and established the lower and upper bound values of genus. The total energy per carbon atom, HOMO-LUMO gap and strain energy of BTA and BTZ multitori have been computed and the results obtained point to BTZ multitori to be at least as stable as C60 what suggests BTZ multitori can be eventually synthesized in laboratory. [...]
2
Content available remote

QSAR of caffeines by similarity cluster prediction

81%
Open Chemistry
|
2014
|
vol. 12
|
issue 3
365-376
EN
A novel QSAR approach based on correlation weighting and alignment over a hypermolecule that mimics the investigated correlational space was performed on a set of 40 caffeines downloaded from the PubChem database. The best models describing log P and LD50 values of this set of caffeine derivatives were validated against the external test set and in a new predictive model by using clusters of similarity.
3
Content available remote

Fullerenes patched by flowers with octagonal core

71%
EN
The aromatic character of three different flowers of general formula [n:(p i,p j)n/2], namely [8:(5,7)4], [8:(6,6)4] and [8:(5,6)4], has been evaluated by means of geometric (HOMA index), energetic (heats of formation) and magnetic criteria (NICS index, exaltation of magnetic susceptibility). Also, the reactivity descriptors within the DFT approach -absolute hardness, electrophilicity, Fukui functions - have been computed. All the different methods used for estimating the aromaticity led to a unitary conclusion. Two fullerene structures, patched by the most stable 8-Sumanene flower, have been designed and evaluated by means of ab initio computations [...]
4
Content available remote

Fullerenes patched by flowers

71%
EN
Stability measures, such as the total energy and the HOMO-LUMO gap, calculated at the Hartree-Fock and DFT levels of theory, and the aromatic character of five circulenes/flowers with a hexagonal core and petals consisting of 5-, 6- and 7-membered rings are investigated. Geometric (HOMA) and magnetic (NICS) criteria are used to estimate the local aromatic character of every ring of the investigated circulenes. The local aromaticity of the coronene and sumanene patches in two tetrahedrally spanned fullerenes were calculated and compared with the HOMA and NICS values of the corresponding isolated circulenes. [...]
first rewind previous Page / 1 next fast forward last
JavaScript is turned off in your web browser. Turn it on to take full advantage of this site, then refresh the page.