We have measured the valence-band photoemission and inverse photoemission spectra of single-walled carbon nanotubes ͑SWNTs͒ with mean radii of 0.7 and 0.64 nm encapsulating C 60 fullerenes ͑peas͒, so-called "peapods." The photoemission spectrum of the C 60 peas in the SWNTs is obtained by subtracting the spectrum of empty SWNTs from the spectrum of the peapod. The structures in the C 60 pea spectra correspond well to those in the spectrum of a C 60 face-centered-cubic solid. No structure is observed at binding energies ranging from the Fermi level ͑E F ͒ to the onset of the highest occupied molecular orbital ͑HOMO͒ peak; the t 1u level of the C 60 peas inside the SWNT stays above E F .

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