Based on the local Shannon entropy concept in information theory, a new measure of aromaticity is introduced. This index, which describes the probability of electronic charge distribution between ...atoms in a given ring, is called Shannon aromaticity (SA). Using B3LYP method and different basis sets (6-31G**, 6-31+G** and 6-311++G**), the SA values of some five-membered heterocycles, C(4)H(4)X, are calculated. Significant linear correlations are observed between the evaluated SAs and some other criteria of aromaticity such as ASE, Lambda and NICS indices. According to the obtained relationships, the range of 0.003 < SA < 0.005 is chosen as the boundary of aromaticity/antiaromaticity. Using B3LYP/6-31+G** level of theory, the Shannon aromaticities for a series of mono-substituted benzene derivatives are calculated and analyzed. It is found that the least standard deviation between the aromaticities and the best linear correlation with the Hammett substituent constants are observed for the new index in comparison with the other indices. Also the values of the new index are evaluated for some substituted penta- and heptafulvenes, which successfully predict the order of aromaticity in these compounds. Applying this index to some non-benzonoids, linear and angular polyacenes also give satisfactory results and prove to be quite suitable for determining the local aromaticity of different rings in polyaromatic hydrocarbons.
In this work, density functional theory (DFT) calculations are performed to investigate the interaction between the melphalan (MP) as a chemotherapy medication and the bare as well as Na Ca ...endohedral encapsulated all‐boron B
40
fullerenes (M@B
40
; M = Na and Ca). The results indicate that this drug interacts with the encapsulated fullerenes stronger than the bare fullerene in both gas and water phases. The electrostatic potential maps indicate that the interaction is charge‐transfer type, occurring from drug to fullerene. The adsorption of six MP molecules onto the considered fullerenes simultaneously indicates the high capacity of these systems for carrying MP drug. The high electronic dipole moments are found for the considered complexes in water phase. Consequently, Na@B
40
and Ca@B
40
systems are introduced as promising innovative candidates for drug delivery of MP drug due to their strong adsorption energies and remarkable solubility in the polar medium. The results might progress new findings in nanomedicine domain.
A New Scale of Electronegativity Based on Electrophilicity Index Noorizadeh, Siamak; Shakerzadeh, Ehsan
The journal of physical chemistry. A, Molecules, spectroscopy, kinetics, environment, & general theory,
04/2008, Letnik:
112, Številka:
15
Journal Article
Recenzirano
By calculating the energies of neutral and different ionic forms (M2+, M+, M, M-, and M2-) of 32 elements (using B3LYP/6-311++G** level of theory) and taking energy (E) to be a Morse-like function of ...the number of electrons (N), the electrophilicity values (ω) are calculated for these atoms. The obtained electrophilicities show a good linearity with some commonly used electronegativity scales such as Pauling and Allred−Rochow. Using these electrophilicities, the ionicities of some diatomic molecules are calculated, which are in good agreement with the experimental data. Therefore, these electrophilicities are introduced as a new scale for atomic electronegativity,. The same procedure is also performed for some simple polyatomic molecules. It is shown that the new scale successfully obeys Sanderson's electronegativity equalization principle and for those molecules which have the same number of atoms, the ratio of the change in electronegativity during the formation of a molecule from its elements to the molecular electronegativity (Δχ/χω) is the same.
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•Li interaction narrows the HLG of C12S8 and C24S12 sulflowers.•Li interaction with sulflowers leads to surprisingly NLO response.•Li interacted sulflowers are introduced as promising ...innovative nonlinear optical material.
Density functional theory (DFT) and time-dependent (TD-DFT) computations have been carried out to study the nonlinear optical response of C24S12 and C16S8 sulflowers with lithium atom. The Li interaction surprisingly causes the remarkable first hyperpolarizability enhancement. Also, the HOMO-LUMO gaps of C24S12 and C16S8 sulflowers are significantly narrowed due to the interaction. The Li interaction with these sulflowers is found to be thermodynamically favorable with negative interaction energies. These sulflowers interacted with Li atom could be introduced as innovative nonlinear optical nanomaterial.
In this work, density functional theory (DFT) calculations are performed to investigate the interaction between the melphalan (MP) as a chemotherapy medication and the bare as well as Na Ca ...endohedral encapsulated all‐boron B40 fullerenes (M@B40; M = Na and Ca). The results indicate that this drug interacts with the encapsulated fullerenes stronger than the bare fullerene in both gas and water phases. The electrostatic potential maps indicate that the interaction is charge‐transfer type, occurring from drug to fullerene. The adsorption of six MP molecules onto the considered fullerenes simultaneously indicates the high capacity of these systems for carrying MP drug. The high electronic dipole moments are found for the considered complexes in water phase. Consequently, Na@B40 and Ca@B40 systems are introduced as promising innovative candidates for drug delivery of MP drug due to their strong adsorption energies and remarkable solubility in the polar medium. The results might progress new findings in nanomedicine domain.
M@B40 (M = Na and Ca) introduced as promising carriers for melphalan (MP) drug. It strongly interacts with Metal@B40 fullerenes in water phase. Remarkable solubility in the aqueous medium is observed for M@B40‐6MP systems. It is found that the release of the MP drug from the surface of the introduced carriers could be occurred in the vicinity of the cancer cells upon the protonation is feasible. To sum up, theses fullerenes might be innovative boron‐based candidates as drug delivery systems.
•5-Fluorouracil strongly interacts with the bare and metals encapsulated B40 fullerenes.•Maximum six 5-fluorouracil molecules can adsorb on the top of B40 fullerene.•Na@B40 and Ca@B40 as promising ...innovative candidates for drug delivery of 5-fluorouracil.•Observing strong adsorption energies and remarkable solubility in the polar medium.
In this work, density functional theory (DFT) calculations are being made to investigate the interaction between the 5-fluorouracil (FU) anticancer drug with the bare and M−encapsulated (M = Na and Ca) all-boron B40 fullerenes. Our results reveal that the FU drug remarkably interacts with both bare and encapsulated fullerene. The electronic structure of the fullerenes is significantly affected via interaction with the FU drug molecule. The decrease of the energy gap of the stable complexes can be used as a chemical signal for determining the FU drug adsorption. The adsorption of six fluorouracil molecules on the top of the Na and Ca encapsulated B40 shows greater adsorption energy than bare fullerene in the gas and water phases. Also, the high dipole moments are found for the considered complexes in the water phase. Consequently, Na@B40 and Ca@B40 are introduced as promising innovative candidates for drug delivery of the Fu molecule due to their strong adsorption energies and great solubility in the polar medium. The results might open new windows in the nanomedicine domain.
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•Assessment of C24N24 fullerene application for anode of metal-ion batteries.•C24N24 fullerene serving as a promising anode material for MIBs.•Remarkable voltage, storage capacity and ...high mobility are observed.
DFT calculations were carried out to determine the potential application of C24N24 cavernous nitride fullerene for the anode electrode for (Li/Na/K/Mg/Ca)-ion batteries (MIBs). Calculated results suggest the C24N24 fullerene as a promising anode material for all these metal-ion batteries. Furthermore, all six cavities of C24N24 fullerene can be decorated by metals, and the storage capacities of 516 and 258 mAh g−1 are obtained for this fullerene. Consequently, both high cell voltages an storage capacity suggest the C24N24 fullerene as an appropriate anode material for alkali and alkali earth metal-ion batteries.
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•Nedaplatin strongly interacts with Li@B40 and Na@B40 fullerenes.•Observing remarkable solubility in the aqueous medium for Li@B40-2NedaPt and Na@B40-2NedaPt systems.•Li@B40 and ...Na@B40 fullerenes introduced as promising carriers for nedaplatin dug.
Density functional theory calculations are carried out to investigate the interaction between the Nedaplatin anticancer drug and the bare and Li, Na encapsulated all-boron B40 fullerenes. The results indicate that this drug remarkably interacts with both bare and encapsulated fullerene. The electronic structure of the fullerenes significantly affected via interaction with drug molecule. The decrease of energy gap of the stable complexes is a chemical signal to determine drug adsorption. The adsorption of two NedaPt molecules on the top of the Li and Na encapsulated B40 shows greater adsorption energy than bare fullerene in the gas and water phases. The high dipole moments are found for the considered complexes in water phase. Consequently, Li@B40 and Na@B40 are introduced as promising innovative candidates for drug delivery of NedaPt molecule due to their strong adsorption energies and remarkable solubility in the polar medium. The results might open new windows in nanomedicine domain.
In the current research, density functional theory calculations were carried out to investigate the potential application of bare and functionalized olympicene molecules (C
19
H
12
) as anode ...materials for Li-ion batteries. The interactions of Li and Li
+
were studied with these molecules and the cell voltages were calculated. The results reveal that the cell voltage of this molecule is greater than some well-known carbon based materials such as C
32
, C
60
, C
70
fullerenes and carbon nanotubes. The functionalization of C
19
H
12
with the electron-donating groups such as OCH
3
, NH
2
, OH enhances the cell voltage. The OCH
3
substituted olympicene exhibits the maximum cell voltage of 1.60 V, which is even greater than that of a (10,10) carbon nanotube.
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