» Articles » PMID: 26815243

Self-assembly of Endohedral Metallofullerenes: a Decisive Role of Cooling Gas and Metal-carbon Bonding

Overview
Journal Nanoscale
Specialty Biotechnology
Date 2016 Jan 28
PMID 26815243
Citations 2
Authors
Affiliations
Soon will be listed here.
Abstract

The endohedral metallofullerene (EMF) self-assembly process in Sc/carbon vapor in the presence and absence of an inert cooling gas (helium) is systematically investigated using quantum chemical molecular dynamics simulations. It is revealed that the presence of He atoms accelerates the formation of pentagons and hexagons and reduces the size of the self-assembled carbon cages in comparison with analogous He-free simulations. As a result, the Sc/C/He system simulations produce a larger number of successful trajectories (i.e. leading to Sc-EMFs) with more realistic cage-size distribution than simulations of the Sc/C system. The main Sc encapsulation mechanism involves nucleation of several hexagons and pentagons with Sc atoms already at the early stages of carbon vapor condensation. In such proto-cages, both Sc-C σ-bonds and coordination bonds between Sc atoms and the π-system of the carbon network are present. Sc atoms are thus rather labile and can move along the carbon network, but the overall bonding is sufficiently strong to prevent dissociation even at temperatures around 2000 kelvin. Further growth of the fullerene cage results in the encapsulation of one or two Sc atoms within the fullerene. In agreement with experimental studies, an extension of the simulations to Fe and Ti as the metal component showed that Fe-EMFs are not formed at all, whereas Ti is prone to form Ti-EMFs with small cage sizes, including Ti@C28-Td and Ti@C30-C2v(3).

Citing Articles

Endohedral Metallofullerenes: Unveiling Synthesis Mechanisms and Advancing Photoelectric Energy Conversion Applications.

Chen W, Huang M, Wu M, Lei Y Top Curr Chem (Cham). 2025; 383(2):14.

PMID: 40085336 DOI: 10.1007/s41061-025-00500-4.


Density-functional tight-binding: basic concepts and applications to molecules and clusters.

Spiegelman F, Tarrat N, Cuny J, Dontot L, Posenitskiy E, Marti C Adv Phys X. 2020; 5(1):1710252.

PMID: 33154977 PMC: 7116320. DOI: 10.1080/23746149.2019.1710252.


Synthesis and Isolation of the Titanium-Scandium Endohedral Fullerenes-Sc2 TiC@Ih -C80 , Sc2 TiC@D5h -C80 and Sc2 TiC2 @Ih -C80 : Metal Size Tuning of the Ti(IV) /Ti(III) Redox Potentials.

Junghans K, Ghiassi K, Samoylova N, Deng Q, Rosenkranz M, Olmstead M Chemistry. 2016; 22(37):13098-107.

PMID: 27459520 PMC: 5029561. DOI: 10.1002/chem.201601655.

References
1.
Zheng G, Witek H, Bobadova-Parvanova P, Irle S, Musaev D, Prabhakar R . Parameter Calibration of Transition-Metal Elements for the Spin-Polarized Self-Consistent-Charge Density-Functional Tight-Binding (DFTB) Method:  Sc, Ti, Fe, Co, and Ni. J Chem Theory Comput. 2015; 3(4):1349-67. DOI: 10.1021/ct600312f. View

2.
Rohmer M, Benard M, Poblet J . Structure, reactivity, and growth pathways of metallocarbohedrenes m(8)c(12) and transition metal/carbon clusters and nanocrystals: a challenge to computational chemistry. Chem Rev. 2001; 100(2):495-542. DOI: 10.1021/cr9803885. View

3.
Porezag , Frauenheim , KOHLER , Seifert , Kaschner . Construction of tight-binding-like potentials on the basis of density-functional theory: Application to carbon. Phys Rev B Condens Matter. 1995; 51(19):12947-12957. DOI: 10.1103/physrevb.51.12947. View

4.
Marks N, Lattemann M, McKenzie D . Nonequilibrium route to nanodiamond with astrophysical implications. Phys Rev Lett. 2012; 108(7):075503. DOI: 10.1103/PhysRevLett.108.075503. View

5.
Dunk P, Kaiser N, Hendrickson C, Quinn J, Ewels C, Nakanishi Y . Closed network growth of fullerenes. Nat Commun. 2012; 3:855. DOI: 10.1038/ncomms1853. View