Electron Energy Loss Spectroscopy with Subnanometer Spatial Resolution on Compositionally Modulated TiN_xMultilayers

EELS and 13C NMR Characterization of Pure Ti2@C80 Metallofullerene

“…The EELS analysis as shown in Figure b also confirms the chemical composition of Ti 2 @C 80 in addition to the mass spectral analysis presented above. The two peaks observed at 465.4 and 460.0 eV correspond to the Ti L 23 -edge . The experimental atomic Ti/C ratio based on the EELS analysis is 2.5 ± 0.4%, which agrees with the theoretical composition of Ti 2 @C 80 (2.5%).…”

Production, Isolation, and EELS Characterization of Ti2@C84 Dititanium Metallofullerenes

“…The EELS spectra of Ti 2 @C 84 isomers (I, II, III) have similar spectroscopic features which involve both the carbon K and Ti L absorption edges. Two sharp peaks located at 459.6 and 465 eV correspond to the Ti L 2,3 (2p) edge . A fine structure of the carbon K (1s) absorption edge starting at 285 eV shares the common features with the other metallofullerenes: a sharp π* peak and humps in a σ* peak with a shoulder around 292 eV.…”

“…EELS is a powerful and efficient technique for investigating the electronic structure of metallofullerene. , The EELS L 23 edge of 3d transition metals is governed by the dipole-allowed transition of 2p electrons to unoccupied 3d states (L 2 : 2p 1/2 → 3d 3/2 , L 3 : 2p 3/2 → 3d 5/2 ) and generally reflects the valence state of the transition-metal atoms. In the Ti compounds, the energy position of the L 3 or L 2 peak varies with the amount of charge transfer from Ti to its adjacent ligands . A detailed analysis of Ti L edge for Ti-metallofullerenes, therefore, gives a measure for the amount of charge transfer from Ti to the fullerene cage.…”

“…Two sharp peaks located at 459.6 and 465 eV correspond to the Ti L 2,3 (2p) edge. 17 A fine structure of the carbon K (1s) absorption edge starting at 285 eV shares the common features with the other metallofullerenes: 18 a sharp π* peak and humps in a σ* peak with a shoulder around 292 eV. Using appropriate cross sections and after background subtraction, normalization of both the edges gives the Ti/C atomic ratio of 2.7 ( 0.3% for the dimetallofullerene Ti 2 @C 84 and 1.7 ( 0.5% for the monometallofullerene Ti@C 90 (see insets in Figure 2b).…”

“…In the Ti compounds, the energy position of the L 3 or L 2 peak varies with the amount of charge transfer from Ti to its adjacent ligands. 17 A detailed analysis of Ti L edge for Ti-metallofullerenes, therefore, gives a measure for the amount of charge transfer from Ti to the fullerene cage.…”