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A fundamental allotrope of carbon that has drawn significant interest in the fields of nanoscience, nanotechnology, condensed matter physics and chemistry, biological physics, materials science and technology, mechanical and electrical sciences, biomedical engineering, and most recently, medical nanotechnology, and nanoneuroscience. Fullerenes are another important allotrope of carbon in addition to graphite, diamond, and nanotubes. The use of molecular topological indices is crucial for bridging the gap between theoretical and practical aspects of chemical characteristics. In recent years, topological indices have been used to investigate the chemical and physical characteristics of fullerenes. This paper uses the $R$ molecular topological index to present topological modeling of the binding energies, heats of formation, shape resonances, and Ramsauer-Townsend minima of fullerenes.

Photoinduced electron transfer processes between C₆₀/C₇₀ and phthalocyanines such as tetra-tert-butylphthalocyanine (H₂TBPc) and its zinc derivative (ZnTBPc) in polar solvents have been studied by observing the transient absorption spectra in the visible and near-IR regions. Upon predominant excitation of TBPcs with a 670 nm laser pulse in polar solvents, growth of the transient absorption bands of and was observed, accompanied by a concurrent decay of the triplet states of TBPcs (³TBPc*). Thus it is confirmed that electron transfer occurs via ³TBPc* in polar solvents. The electron transfer rate constants and efficiencies of electron transfer via ³ZnTBPc* are greater than those via ³H₂TBPc* owing to the electron ejection ability of ³ZnTBPc*. Solvent effects on the forward and backward electron transfer processes have been evaluated.

Clusters of C₆₀ fullerenes are (multi)-ionised in collisions with O⁵⁺ projectiles at a collision energy of 100 keV. The dominant fragmentation channels are analysed by time-of-flight mass spectrometry for different cluster size distributions. Singly charged , ions are found to be the dominant fragments, in 25% connected with the loss of one or more C₂-units. This result is explained by the large charge mobility in fullerene clusters. Doubly charged fragments, in form of and , contribute to the observed spectrum with less than 5–10% only and are mainly attributed to the fragmentation of dimers. Singly charged small carbon clusters in the size range n = 7 to 19 are formed with low kinetic energies indicating the importance of thermal dissociation processes. The present experiments confirm earlier conclusions on the charge mobility in fullerene clusters.

This paper gives a survey of physical phenomena manifesting themselves in electron and photon collisions with atomic clusters. The emphasis is made on electron scattering, photoabsorption and photoionization of fullerenes and metal clusters, however some results are applicable to other types of clusters as well. It is demonstrated that the diffraction and interference phenomena play an important role in the processes of clusters interaction with photons and electrons. The essential role of the multipole surface and volume plasmon excitations is elucidated in the formation of electron energy loss spectra on clusters as well as in the total inelastic scattering cross sections and in multiphoton absorption regime. Attention is paid to the elucidation of the role of the polarization interaction in low energy electron-cluster collisions. This problem is considered for the electron attachment to metallic clusters and the plasmon enhanced photon emission. The mechanisms of electron excitation widths formation and the relaxation of electron excitations in metal clusters and fullerenes are discussed.

The fullerene cage clusters C₆₀ and C₇₀ become magnetic and half metallic when doped with B and N atoms. The five-atom transition metal clusters of Mn, Fe, Co, and Ni encapsulated inside fullerene cages have higher magnetic moment, while that of Cr become nonmagnetic as compared to corresponding isolated clusters. These clusters encapsulated inside fullerene cages get distorted. The distortion in a cluster inside C₇₀ is larger as compared to that inside C₆₀, C₅₉B, and C₅₉N cages. These clusters also distort the hexagons and pentagons of fullerene cages. The fullerene cages expand but retain their shapes. The energy calculations show that Mn and Cr clusters encapsulated inside C₆₀ and C₅₉N are stable.

Photoconductive and photorefractive characteristics of fullerene- and nanotubes-doped organic thin films based on conjugated organics, such as polyimide, polyaniline, pyridine, etc. have been studied. In addition, the liquid crystal mesophase with nanoobjects has been investigated. The increase of the charge carrier mobility of nanosensitized organics has been established. The nonlinear refraction and cubic nonlinearity have been investigated at wavelength of 532 nm via four-wave mixing technique using Raman-Nath diffraction regime. The thin holographic grating has been written at the spatial frequencies placed in the range of 90-150 mm^-1. The energy density has been chosen in the range of 0.1-0.9 J×cm^-2. The correlation between photoconductive and nonlinear optical parameters has been revealed. The nanostructured materials can be proposed for different area of nano- and microelectronic applications.

The interaction between C₆₀ and quantum dots (QDs) has attracted much attention recently due to its potential applications in solar cells, for example, as a promising renewable energy source. In this paper, monolayer self-assembled CdSe/ZnS core/shell QDs films were prepared and drop-coated with different amounts of C₆₀. A significant photoluminescence quenching and an emission lifetime reduction were observed in the QDs-C₆₀ composite films, and the quenching efficiency was increased with the increasing of the C₆₀ content. Together with the reduced emission lifetime, the results here provide direct evidence for the charge transfer process in the QDs-C₆₀ system.

The present paper deals with the comprehensive studies of phonon dynamics in alkali metal (M) doped C₆₀ (MC₆₀) solids in fcc phase using a rigid ion model with pairwise interionic interaction potential. The investigations include the computation of the phonon density of states, the specific heat, the Gruneisen parameters, thermal expansion and thermal expansion coefficient and the phonon-dispersion curves of RbC₆₀. The analysis incorporates the van der Waal's and Coulomb interactions for alkali metal–C₆₀ as well C₆₀–C₆₀ molecule and show fairly good agreement with reported inelastic neutron scattering results for RbC₆₀. We have found that thermal expansion coefficient at room temperature is in the range 4.3–6.2 × 10^-5K^-1, which is of the order of pure C₆₀ solid (6.1 × 10^-5K^-1). Comparing the thermal expansion coefficient of different alkali-doped solids, we conclude that doping decreases anharmonicity in general, and further it decreases with increase in size of the alkali metal. The results have been found to present an overall consistent interpretation of the available experimental data.

To date, superconductivity in fullerides has been almost exclusively tuned by (chemical or physical) pressure control of the conduction bandwidth, W at half filling. This contrasts sharply with the extensive control of the superconducting transition temperature, $T_c$ in atom-based superconductors such as the cuprates and iron pnictides and chalcogenides via changes in valence (bandfilling). Here, we investigate the effect of doping away from the exactly half-filled ${\text{C}}_{60}^{3-}$ level in quaternary face-centered-cubic (fcc) — structured fulleride solids with nominal composition (${\text{Rb}}_{2.5-x}$Cs_x)${\text{Ba}}_{0.5}$${\text{C}}_{60}$ ($0\le x\le 2.5$), in which divalent ${\text{Ba}}^{2+}$ ions partially replace monovalent alkali ${\text{Rb}}^{+}$/${\text{Cs}}^{+}$ ions. The resulting charged-modified fullerides in which the $t_{1u}$ bandwidth is also varied with changing x show a dome-shaped dependence of $T_c$ on interfullerene separation in analogy with their half-filled antecedents. However, following electron injection beyond half-filling, the superconductivity dome is found to shift towards shorter interfullerene separations, i.e. towards increased conduction bandwidths.

Carbon atoms can connect with themselves and with other atoms (both electronegative and electropositive elements) in various ways. Thanks to these abilities, the diversity of carbon compounds is increasing day by day. This growth was even faster after the discovery of carbon nanoallotropes, i.e. carbon nanotubes, fullerenes, and graphene. At present, these carbon nanoallotropes are widely studied, and new hybrid structures have been synthesized based on these nanoallotropes. Hybrid structures formed by the covalent bond of fullerenes to the outside carbon nanotubes are called carbon nanobuds (CNBs). Development of synthesis methods, computational calculations, and the study of CNB properties was much faster than other hybrid structures. However, only fewer articles on CNBs have been published in recent years. CNBs show a synergistic effect and have the unique properties of the carbon nanoallotropes from which they formed. This review discusses CNBs and reports the recent research on CNBs, mostly after 2016.

Construction of periodic fulleroids (including covering polygons other than the classical pentagons and hexagons) is achieved by several coupling procedures. A constitutive typing enumeration for topologically periodic fulleroids is given. π-electronic periodicity of several series of tubulenes is rationalized in terms of some "rules of thumb". The strain energy of these nonplanar molecules was evaluated from the pyramidalization angles of the sp² carbon atoms by the POAV1 procedure. Semiempirical PM3 calculations support the presented spectral data.

We used carbon soot produced by electrical arc method. Fullerenes, mainly C₆₀ and C₇₀, were Soxhlet extracted from collected soot with chlorobenzene, by modified procedure yielding 5.8% of the extract. Chlorobenzene fullerenes extract was then separated on an active alumina column, modifying the existing methods, by elution with hexane and xylene/hexanes mixtures in determined ratios and orders. Buckminsterfullerene C₆₀ was identified in the first purified fraction using EI mass spectrometry, IR and UV/vis methods. The second and the third purified fraction, carbon soot and chlorobenzene soot extract were characterized by IR and UV/vis methods. Identifications of fullerenes in purified and unpurified forms were analyzed and compared.

In this paper, we investigate a rotating fullerene molecule with Ih symmetry within the framework of non-inertial space-times. We use a low-energy geometric theory to describe the molecule as a two-dimensional spherical space of Gödel type. Using the well-known fictitious ’t Hooft–Polyakov monopole to decouple the doublet associated with the lattice, we employ the Dirac factor method to derive a geometric phase for the fermions in the system. We also discuss the chronology protection feature of the phase through specific geometric considerations for the system.

Recent advances in electron transfer chemistry of electron donor-acceptor ensembles reported containing porphyrins and metalloporphyrins reported in ICPP-2 are reviewed briefly by focusing on the fundamental aspects of electron transfer reactions.

The fabrication of high quality, robust and photoactive ITO electrodes is reported. Electrostatic and van-der-Waals interactions have been used for the step-by-step deposition of layers containing a fullerene-porphyrin dyad as the active layer.

Bislactone linked porphyrin-fullerene dyads show promising photophysical properties for mimicking photosynthesis. Optical and transient displacement current investigations of the dyads demonstrate efficient intramolecular electron transfer from porphyrin to fullerene with the lifetime of the charge transfer state on the order of a few nanoseconds in low polarity solvents. Solvent polarity effect on the yield of charge separation and conformations in the charge transfer state are investigated in detail. The facile synthesis could readily be applied to constructing extended compounds with high yields of photoinduced charge separation.

The complexes of cobalt(II) tetraphenylporphyrin (Co^IITPP) with fullerenes C₆₀, C₇₀ and C₆₀(CN)₂ are presented. It is shown that Co^IITPP forms complexes with fullerenes in different solvents: [Co^IITPP•fullerene•solvent] (solvent = C₆H₆, C₆H₅Me, C₆H₄Cl₂, CS₂, CHCl₃). The use of additional donors (Cp₂Fe, Cr⁰(C₆H₆)₂, and TDAE) in the synthesis of Co^IITPP/fullerene complexes allows one to obtain multi-component complexes ranging from neutral [(Co^IITPP•Py)₂•Cp₂Fe•fullerene•solvent] to ionic [Co^IITPP•(D₂^•+)•(fullerene^•−)•solvent] (D₂ = Cr^I(C₆H₆)₂, TDAE). The interaction of Co^IITPP with neutral and negatively charged fullerenes is considered. The neutral Co^IITPP/fullerene complexes are characterized by a secondary M…C(fullerene) bonding with the shortest Co…C contacts in the 2.69-2.82 Å range and noticeable changes in the electronic structure of the parent components. At the same time, σ-bonding is observed in ionic complexes between Co^IITPP and fullerene radical anions with the shortened Co…C contacts being in the 2.28-2.32 Å range. The resulting (Co^IITPP•fullerene⁻) anions are diamagnetic. The σ-bonding is relatively weak and the (Co^IITPP•fullerene⁻) anions begin to dissociate above 200 K.

Recent advances in electron transfer chemistry of supramolecular electron donor-acceptor assemblies – containing porphyrins and metalloporphyrins – in connection with ICPP-3 are reviewed briefly by focusing on aspects of electron and energy transfer reactions.

Two pyropheophorbide a units were attached via a malonate addition reaction to the [60]fullerene core to give a trichromophoric system. Also, in a different approach two pyropheophorbide a moieties were coupled to a hexasubstituted [60]fullerene diol. The mono-adduct was very light and oxygen sensitive whereas the corresponding hexaadduct showed a much higher stability.

The ‘bottom-up’ strategy is an attractive and promising approach for the construction of nanoarchitectures. Supramolecular assemblies based on non-covalent interactions have been explored in an attempt to control surface properties. In this minireview, we focus on advances made in the past three years in the field of scanning tunneling microscopy (STM) on supramolecular assembly and the function of porphyrins, phthalocyanines, and fullerenes, non-covalently bound on metal single crystal surfaces. Well-defined adlayers, consisting of porphyrin and phthalocyanine for the design of supramolecular nanoarchitectures, supramolecular traps of C₆₀ on hydrogen bond networks, a unique approach for controlling molecular orientation by a 1:1 supramolecularly assembled film consisting of C₆₀ and the related derivatives and metallooctaethylporphyrins, and nanoapplications of fullerenes, either induced by tip manipulation or driven by thermal fluctuations at surfaces, were clearly visualized by STM.