1. Band Structure Of YBCO

2. Crystal Structure of YBCO

3. Band Structure of YBCO using LDA method

4. Breaking down of the band structure (LMTO)

5. Band structure for Kz = 0 along the triangle ( Kx a/ π, Ky b/ π)
Consider only Cu – d and O – p orbital
Band structure consisting: anti-bonding pdσ chain
anti-bonding pdσ even chain
anti-bonding pdσ odd chain

6. Band structure for Kz = π/c along the triangle ( Kx a/ π, Ky b/π)

7. c, e, g, i : considering odd linear combinations.
d, f, h, j : considering even linear combinations.
e, f : removing the interaction of Cu zx and
Cu zy and O z orbital.
i, j : removing Cu zx and Cu zy and
retained only the O z orbital.

8. Conclusion
Most important plane in YBCO is CuO plane near to Y.( no band gap)