XPS Study of Mechanically Activated YBa₂Cu₃O_6+δ and NdBa₂Cu₃O_6+δ

Table 2

The positions of the characteristic XPS lines of barium compounds.

Electron orbital	BaCO3	Ba(OH)2	Y-123	Y2BaCuO5
	Binding energy, eV
Ba 3d5/2	779.9 [16, 17]; 779.8*	781.3 ± 0.1; [18, 19]	777.7 ± 0.1; [20–23]	781.9*
Ba 4d5/2	89.3*		87.5; [22]
Y 3d5/2			156.0 ± 0.2; [21, 24, 25]	158.7*
Cu 2p3/2			933.5; [21, 26]	935.6*
O 1s	531.4 ± 0.1; [16, 17]; 531.4*	531.2 эB; [27]	528.45 ± 0.05 эB; [20–23]	(529.1, 531.3)*
C 1s	289.25 ± 0.15 эB; [16, 17]; 289.4*

∗Our data.