Surface stoichiometry and valence electronic structure of YBa2Cu3O7-x.

Presents information on a study which discussed x-ray photoemission data from YBa[sub2]Cu[sub3]O[sub7-x] showing that the measured composition and the electronic structure changes upon the photoelectron escape depth. Sample preparation; Valence band measurements performed; Ways the absence of a surface may modify the electronic distribution in the outer layers.