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Two nickel porphyrin-C${}_{60}$ dyads, viz., meso-(tri(toly)porphyrinato)nickel-C${}_{60}$ (NiTTP-C${}_{60}$), and meso-(tri(triphenylamine)porphyrinato)nickel-C${}_{60}$ (NiTPA-C${}_{60}$) were newly synthesized and studied by various techniques including optical absorption, electrochemistry, DFT and time dependent-DFT (TD-DFT) and femtosecond transient absorption, to establish the photochemical events. While electrochemical studies examined the redox properties of the dyads, the spectrum of the radical ion species was obtained from the chemical oxidation method. Although energetically photoinduced energy and/or electron transfer from excited nickel porphyrin to C${}_{60}$ was possible, femtosecond transient absorption studies were not conclusive of the occurrence of either of these events. The low-lying orbitals of the d⁸-configured nickel porphyrin were attributed to this phenomenon. It appears that nonradiative decay of the excited nickel porphyrin via the low-lying orbitals dominated the relaxation path instead of either energy or electron transfer involving covalently linked C${}_{60}$, including NiTPA-C${}_{60}$ having an easily oxidizable porphyrin. TD-DFT studies further supported this mechanism, revealing that the excited charge transfer was only possible in these dyads from the significantly higher electronic excited states, viz., the 35^th and 39^th excited states in the cases of NiTTP-C${}_{60}$ and NiTPA-C${}_{60}$. The present study highlights the significance of low-lying orbitals in metalloporphyrins to suppress energy and electron transfer events in covalently linked donor-acceptor systems.

A series of new phytochlorin–fullerene dyads was prepared. Synthetic pathway includes attachment of glycine to aldehyde-containing phytochlorins via reductive amination, where 3- and 7-carbonyl-substituted pheophorbides exhibit surprisingly different reactivity. The appropriate conditions of reactions (e.g. solvents and reducing agents) were determined in each case.

A photovoltaic photodetector harnessing near infrared band gap absorption by thin films of post-synthetically sorted semiconducting single walled carbon nanotubes (s-SWCNTs) is described. Peak specific detectivity of 6×10¹¹ Jones at -0.1 V bias at 1210 nm is achieved using a heterojunction device architecture: indium tin oxide/ ca. 5 nm s-SWCNT / 120 nm C₆₀ / 10 nm 2,9-dimethyl-4,7-diphenyl-1,10-phenanthroline (BCP) / Ag. The photodiodes are characterized by a series resistance of 2.9 Ω cm² and a rectification ratio of 10⁴ at ±1V. These results are expected to guide the exploration of new classes of solution-processable, mechanically flexible, integrable, thin film photovoltaic photodetectors with tunable sensitivity in the visible and infrared spectra based on semiconducting carbon nanotubes.

In this paper, the initial stage of films assembled by energetic C₃₆ fullerenes on diamond (001)–(2 × 1) surface at low-temperature was investigated by molecular dynamics simulation using the Brenner potential. The incident energy was first uniformly distributed within an energy interval 20–50 eV, which was known to be the optimum energy range for chemisorption of single C₃₆ on diamond (001) surface. More than one hundred C₃₆ cages were impacted one after the other onto the diamond surface by randomly selecting their orientation as well as the impact position relative to the surface. The growth of films was found to be in three-dimensional island mode, where the deposited C₃₆ acted as building blocks. The study of film morphology shows that it retains the structure of a free C₃₆ cage, which is consistent with Low Energy Cluster Beam Deposition (LECBD) experiments. The adlayer is composed of many C₃₆-monomers as well as the covalently bonded C₃₆ dimers and trimers which is quite different from that of C₂₀ fullerene-assembled film, where a big polymerlike chain was observed due to the stronger interaction between C₂₀ cages. In addition, the chemisorption probability of C₃₆ fullerenes is decreased with increasing coverage because the interaction between these clusters is weaker than that between the cluster and the surface. When the incident energy is increased to 40–65 eV, the chemisorption probability is found to increased and more dimers and trimers as well as polymerlike-C₃₆ were observed on the deposited films. Furthermore, C₃₆ film also showed high thermal stability even when the temperature was raised to 1500 K.

Two batches of C₆₀ films were grown at different growth rate, using a vacuum deposition technique. X-ray diffraction patterns indicate both films have preferential (111) orientation. We measured their dielectric constant and loss factor from 80K to room temperature, and observed distinct broad and asymmetric loss peaks, attributed to orientational glass transition. The apparent activation energy was determined as 344.4 and 304.8 meV for film A and B respectively, larger than the value 280 meV in bulk C₆₀. Ngai's correlated-state model is used to simulate relaxation spectrum, and the real activation energies were calculated, which agree with the reported activation value in bulk C₆₀ very well. We propose that the structure imperfection have contributed additional dipole correlation interactions, which make the relaxation behavior of our C₆₀ films deviate from that of bulk C₆₀.

We present experimental measurements of time-dependent photoelectron spectra observed in thermionic emission of small carbon cluster anions and C₆₀ fullerenes. The combination of photoelectron velocity-map imaging with time-gated detection allowed to resolve delayed electron emission at different stages of the emission process. This unique capability allows us to analyze pure thermionic energy spectra under well-defined conditions. Experimental spectra are analyzed within the framework of the detailed balance theory.

In highly charged ion Xe^q+ (q=8, 15, 20, 25, 30) on C₆₀ collisions (v = 0.19 a.u.), the energy loss of projectiles in frontal collisions has been measured by analyzing the kinetic energy of scattered ions. Using singly charged projectiles He⁺, the measurement of the ejected electron number provides information on the electronic energy deposition during the fontal collision on the C₆₀ target.

Collective dynamics of a strongly correlated nano-fluid of fullerenes, C₆₀ having number density 0.945 particles/nm³ at 1850 K has been predicted using the sphericalized inter-fullerene interaction and the self-consistent microscopic theory of fluids. The dynamical structure factors have been computed to yield much different dispersion relation of the collective excitations from that of the Lennard–Jones type fluid. The wave-vector dependent longitudinal viscosity of the nano-fluid has also been reported.

The present study is geared towards investigating methods to increase the tendency of fullerene structures to aggregate with biological systems. To accomplish this task, the encapsulation of metals inside a fullerene structure was performed. The calculations performed demonstrate that the Ca@C₆₀ structure leads to stronger interactions with amino acids at the DFT-BLYP/DND level of theory. Correlations of the dissociation energies, HOMO/LUMO band gaps and hardness are discussed.

The structural and electronic properties of endohedral fullerenes formed by encapsulation of each of the group V elements inside the buckminsterfullerene cage have been investigated. The calculations reveal that all these species are thermodynamically stable, though the formation of Sb@C₆₀ and Bi@C₆₀ is slightly endothermic. The central atom preserves its electronic configuration and the quartet state. The energy gap and energy levels are perturbed by the inclusion of a foreign atom. The band gap of Sb@C₆₀ and Bi@C₆₀ is found to be significantly smaller than pristine C₆₀, suggesting the reactivity of these complexes.

Fullerene grafted poly (methylmethacrylate) polymers have been studied using X-ray diffraction and raman spectroscopy to analyze their polymeric structure. The electrical properties of prepared polymers have also been studied. The X-ray diffraction and raman spectroscopy pattern of pure buckminster fullerene (C₆₀) has been compared with prepared polymeric samples. Raman spectroscopy indicates that a structural change occurs due to grafting. The vibrations in the relative intensity of peaks and shifts in energy are observed. The lower scattering efficiency of pure fullerene (C₆₀) is observed at 1468 cm^-1.The values for poly (methylmethacrylate) are observed at 3000 cm^-1. The result show a large shift in the intense raman spectral region of fullerene-based poly (methylmethacrylate) which lies between 2500 cm^-1 and 3000 cm^-1. X-ray diffraction shows an unusual variation in crystallite size of polymeric samples. Generally it has been observed that polymers are insulators, but noticeably fullerene-based poly (methylmethacrylate) show conducting behavior.

The pressure dependent changes in transition temperature (T_c) of alkali doped C₆₀ superconductor has been studied theoretically considering the combination of phonon mediated mechanism and high energy electronic interaction mechanism. The latter mechanism involves bond polarization in interaction with conduction electrons. The expression for T_c, isotope effect coefficient (α) and (dT_c/dP)_P has been obtained to explain the observed experimental results of alkali doped C₆₀. A good agreement has been found in experimental (T_c) and (dT_c/dP)_{P = 0} values and calculated values.

Superatomic molecular orbitals (SAMOs) in C₆₀ are ideal building blocks for functional nanostructures. However, imaging them spatially in the gas phase has been unsuccessful. It is found experimentally that if C₆₀ is excited by an 800-nm laser, the photoelectron casts an anisotropic velocity image, but the image becomes isotropic if excited at a 400-nm wavelength. This diffuse image difference has been attributed to electron thermal ionization, but more recent experiments (800 nm) reveal a clear nondiffuse image superimposed on the diffuse image, whose origin remains a mystery. Here we show that the nondiffuse anisotropic image is the precursor of the f SAMOs. We predict that four 800-nm photons can directly access the 1f SAMO, and with one more photon, can image the orbital, with the photoelectron angular distribution having two maxima at 0° and 180° and two humps separated by 56.5°. Since two 400-nm photons only resonantly excite the spherical 1s SAMO and four 800-nm photons excite the anisotropic 1f SAMO, our finding gives a natural explanation of the nondiffuse image difference, complementing the thermal scenario.

The localization of the valence electron of $H$, $Li$ and $Na$ atoms enclosed by three different fullerene molecules is studied. The structure of the fullerene molecules is used to calculate the equilibrium position of the endohedrally atom as the minimum of the classical $(N+1)$-body Lennard–Jones potential. Once the position of the guest atom is determined, the fullerene cavity is modeled by a short range attractive shell according to molecule symmetry, and the enclosed atom is modeled by an effective one-electron potential. In order to examine whether the endohedral compound is formed by a neutral atom inside a neutral fullerene molecule $X$@$C_N$ or if the valence electron of the encapsulated atom localizes in the fullerene giving rise to a state with the form $X^{+}$@$C_N^{-}$, we analyze the electronic density, the projections onto free atomic states and the weights of partial angular waves.

In the present paper, we have done a systematic study of structural and electronic properties of endohedrally doped C${}_{60}$ with Al and Ga atoms using density functional theory (DFT) with the help of Spanish initiative for electronic simulation with thousands of atoms (SIESTA) package in the generalized gradient approximation (GGA). The parameters calculated are binding energy/dopant atom, vertical ionization potential (VIP), vertical electron affinity (VEA), HOMO–LUMO gap and charge transfer. The stabilized ground state structures of Al${}_n$@C${}_{60}$ ($n=1$–10) and Ga${}_n$@C${}_{60}$ ($n=1$–10) show that a maximum of nine Al or Ga atoms can be encapsulated in C${}_{60}$ without distorting the cage significantly. Mulliken charge analysis shows an electron transfer from the metal dopant to the cage surface, except for Al${}_n$ ($n=7$–10). The endohedral metal clusters adopt a more compact shape when inside C${}_{60}$, compared to its free-state configuration and its symmetry. The study of HOMO–LUMO gap reveals that the gap decreases with the increase in number of dopant atoms inside C${}_{60}$.

The detonation of carbon- or nitrogen-containing explosives not only produces powerful shock waves but also provides elemental building blocks and a unique high-pressure and high-temperature physical environment for the construction of various nanostructures. This review highlights the situation and key progresses in the detonation approach towards diamond nanoparticles, graphitic carbon nanotubes, fullerene molecules, and gallium nitride nanocrystals. Further extension of the peaceful-use detonation applications and rational reactor design are also proposed.

The analytic expressions for equation of state and internal energy for the poly-exponential solid have been derived based on the analytic mean-field potential (AMFP) method. The formalism is applied to the fcc C₇₀ solid. One set of potential parameters are determined through fitting the experimental compression data¹ of C₇₀ up to 1 GPa and at temperature 365 K. The difference between the well depth for C₇₀ molecules and that for C₆₀ molecules is fairly small. The thermo-physical properties including the isothermals, thermal expansivity, isochoric heat capacity, Helmholtz free energy and internal energy have been calculated and analyzed. The theoretical results are in good agreement with the experimental data of C₇₀ solid available. Based on the results of our calculations, we may also predict the behaviors of C₇₀ at extreme conditions.

Dielectric properties and electrical conductivity of different concentrations of Poly methylmethacrylate (PMMA)/fullerene C60 composites have been reported at room temperature in the frequency range from 1 kHz to 5 MHz. The frequency dependence of complex permittivity, ε*, and complex electrical modulus, M*, have been measured. Frequency dependence of dielectric constant, follows Cole–Cole dielectric relaxation equations, was investigated diagrammatically. Moreover, equations of Tsangaris et al. have been tested for our case to describe the dielectric behavior of particulate polymeric composite containing fillers which give a satisfactory agreement taking into account the variation of the aspect ratio with the volume fraction of fullerene C60 doped in the PMMA matrix.

Hydrogen storage is a key factor for the application of hydrogen energy. From first principle calculation, we have acquired the energy barrier for hydrogen molecules to pass through the hexagonal rings and pentagonal rings of the fullerene. Then the absorption energy and energy barrier are used to analyze the hydrogen adsorption capacity of the fullerene family and their hydrides. We have also studied the hydrogen storage properties of the fullerene family and their hydrides by grand canonical Monte Carlo method. It is found that the weight density of hydrogen storage at ambient temperature and pressure can reach 7.71 wt.%. The results show that it is difficult for hydrogen to get into the carbon cage of the fullerene because of the high energy barrier, while it is beneficial to destroy the fullerene structure for the processes of absorption and desorption. Meanwhile, fullerene hydrogenation is an effective method to improve the hydrogen storage properties. Our study facilitates the design and synthesis of hydrogen storage materials, and provides theoretical support to improve the hydrogen storage capability for materials.

Complex drugs based on C${}_{60}$ fullerence and pyrrole derivatives are promising for the development of antitumor and anti-inflammatory agents for use in targeted therapy, but have little efficiency in the synthesis of such complexes and have virtually no stable synthesis products with fullerene. The stability of the nanocomplex based on [60] PCBA and the intermediate compound based on “$1H$-pyrrole-2,5-dione” effective for the synthesis of targeted therapeutic agents was investigated by means of numerical calculations. The application of quantum-chemical methods in the Gaussian package establishes the stability of the nanocomplex at human body temperatures, the possibility of using such complexes for further study of the therapeutic properties of the individual components of the decomposition products of the nanocomplex.