Search results for "FULLERENE"
showing 10 items of 197 documents
From small to medium and beyond: a pragmatic approach in predicting properties of Ne containing structures
2013
In this study, we outlined a pragmatic approach for structural studies leading to better understanding of polycarbon structures using 21Ne as a nuclear magnetic resonance (NMR) probe. 21Ne NMR parameters of a single neon atom and its dimer were predicted at the CCSD(T) level in combination with large basis sets. At a lower level of theory, an interaction of neon atom with 1,3-cyclopentadiene ring and with five- and six-membered rings in carbazole was studied using the restricted Hartree–Fock (RHF) and density functional theory (DFT) combined with smaller basis sets. The RHF and DFT modelling of neon interaction with nanosized objects were performed on cyclacenes and selected fullerenes.
Efficient Modeling of NMR Parameters in Carbon Nanosystems
2015
Rapid growth of nanoscience and nanotechnology requires new and more powerful modeling tools. Efficient theoretical modeling of large molecular systems at the ab initio and Density Functional Theory (DFT) levels of theory depends critically on the size and completeness of the basis set used. The recently designed variants of STO-3G basis set (STO-3Gel, STO-3Gmag), modified to correctly predict electronic and magnetic properties were tested on simple models of pristine and functionalized carbon nanotube (CNT) systems and fullerenes using the B3LYP and VSXC density functionals. Predicted geometries, vibrational properties, and HOMO/LUMO gaps of the model systems, calculated with typical 6-31G…
Overcoming the Insolubility of Molybdenum Disulfide Nanoparticles through a High Degree of Sidewall Functionalization Using Polymeric Chelating Ligan…
2006
Study of the electrochemical and optical properties of fullerene and methano[60]fullerenediphosphonate derivatives in solution and as self-assembled …
2014
Four methanofullerenes with phosphonate groups attached to a C60 core were synthesized to probe their electrochemical and optical properties both in solution and as self-assembled monolayer structures (SAMs). As the methano[60]fullerenediphosphonate is a water soluble derivative of the fullerene it has high potential as an imaging molecule in biological applications and in optoelectronics. For the processing of fullerene based SAMs different electrode substrates (ITO, Au and Si) with specific anchoring groups (zirconium, cysteamine and amino-silane) were used. The formation of the C60-SAMs to the surfaces were investigated by atomic force microscopy (AFM), infrared spectroscopy, contact ang…
Table of Periodic Properties of Fullerenes Based on Structural Parameters.
2004
The periodic table (PT) of the elements suggests that hydrogen could be the origin of everything else. The construction principle is an evolutionary process that is formally similar to those of Darwin and Oparin. The Kekulé structure count and permanence of the adjacency matrix of fullerenes are related to structural parameters involving the presence of contiguous pentagons p, q and r. Let p be the number of edges common to two pentagons, q the number of vertices common to three pentagons, and r the number of pairs of nonadjacent pentagon edges shared between two other pentagons. Principal component analysis (PCA) of the structural parameters and cluster analysis (CA) of the fullerenes perm…
Physical interaction between tip and molecules in scanning force microscopy imaging of adsorbed C60 and fullerene tubules
1994
After the discovery of C60, a large family of fullerene molecules was also identified. Among them, elongated fullerenes are formed by the tubular assembly of carbon atoms. The van der Waals bonds between fullerene molecules are due to the correlations between fluctuating charge densities inside the molecules. The interaction is then dominated by collective excitations which are sensitive to the shape of the molecules. Therefore, van der Waals attraction is expected to be modified when considering successively spherical C60, C70 and more elongated fullerenes (tubules). This paper presents self‐consistent computations of the van der Waals interaction between a (111) diamond probe tip and vari…
Molecular polarizability of fullerenes and endohedral metallofullerenes
2002
The interacting induced dipoles polarization model implemented in our program POLAR is used for the calculation of the molecular dipole µ and tensor quadrupole moments and also the dipole–dipole polarizability . The method is tested with Scn, Cn (fullerene and graphite) and endohedral Scn@Cm clusters. The polarizability is an important quantity for the identification of clusters with different numbers of atoms and even for the separation of isomers. The results for the polarizability are of the same order of magnitude as from reference calculations performed with our version of the program PAPID. The bulk limit for the polarizability is estimated from the Clausius–Mossotti relationship. The…
Role of the bridge in photoinduced electron transfer in porphyrin-fullerene dyads.
2015
The role of π-conjugated molecular bridges in through-space and through-bond electron transfer is studied by comparing two porphyrin-fullerene donor-acceptor (D-A) dyads. One dyad, ZnP-Ph-C60 (ZnP = zinc porphyrin), incorporates a phenyl bridge between D and A and behaves very similarly to analogous dyads studied previously. The second dyad, ZnP-EDOTV-C60, introduces an additional 3,4-ethylenedioxythienylvinylene (EDOTV) unit into the conjugated bridge, which increases the distance between D and A, but, at the same time, provides increased electronic communication between them. Two essential outcomes that result from the introduction of the EDOTV unit in the bridge are as follows: 1) faster…
Catalytic Synergism in a C60IL10TEMPO2 Hybrid in the Efficient Oxidation of Alcohols
2014
A novel fullerene (5:1)hexakisadduct bearing two 2,2,6,6-tetramethylpiperidine 1-oxyl (TEMPO) radicals and ten 1-propyl-3-methylimida- zolium bromide moieties has been synthesized and characterized. Such an C60IL10TEMPO2 hybrid has been successfully employed as a catalyst in the se- lective oxidation of a wide series of alcohols and is highly active at just 0.1 mol% loading. Moreover, it can be easily recovered by adsorption onto a multi- layered covalently-linked SILP phase (mlc-SILP) through a "release and catch" approach and reused for up to 12 cycles without loss in efficiency. Inter- estingly, a catalytic synergistic effect of TEMPO and imidazolium bromide moieties combined in the same…