Electronic structures of PrBa 2 Cu 3 O 7 , Pr 2 Ba 4 Cu 7 O 15− y ( y = 0, 1), and PrBa 2 Cu 4 O 8 based on LSDA + U method

The electronic structures of PrBa 2 Cu 3 O 7 (Pr123), Pr 2 Ba 4 Cu 7 O 15− y (Pr247), and PrBa 2 Cu 4 O 8 (Pr124) cuprates have been obtained using density‐functional theory in the local spin density approximation plus onsite Coulomb interaction (LSDA +  U ). Onsite Hubbard correlation, U , has been considered for Pr‐f and Cu‐d orbitals and the effects of considering these correlation corrections on the PrO hybridizations have been inspected. Results imply that the Pr ionization state in Pr123 system is constituted from two different configurations, and the energy of the f states in these two configurations has an important role in superconductivity properties of the system. Our calculations also show that in both Pr124 and Pr247 systems, suppression of superconductivity is weaker than that in the Pr123 system. This occurs due to the weaker PrO bond in both Pr124 and Pr247 systems. The role of the double chain and single chain on the conduction properties of these compounds has been investigated. We have also studied the effect of oxygen deficiency in Pr247 system, which seems to revive superconductivity in this system. Investigating the hole carriers in the CuO 2 plane shows a correlation between superconductivity suppression and hole decrement in the planes.