The electronic structure of high-quality TiSe2 and TiS2 crystals has been investigated using angle-resolved photoemission with Hei, Hen, and Nei resonance radiation. Results compare well with recent selfconsistent energy-band calculations although differences occur which may be due to the threerather than two-dimensional nature of specific bands. Occupied d states at the zone edge are observed in both materials.A small overlap with the s/p valence band at I is observed in the case of TiSe, in approximate agreement with other workers. TiS, appears to be a defect semiconductor with a band gap of 0.3+0,2 eV.

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