Combined density-functional and dynamical cluster quantum Monte Carlo   calculations for three-band Hubbard models for hole-doped cuprate   superconductors
  Using a combined local density functional theory (LDA-DFT) and quantum Monte Carlo (QMC) dynamic cluster approximation approach, the parameter dependence of the superconducting transition temperature Tc of several single-layer hole-doped cuprate superconductors with experimentally very different Tcmax is investigated. The parameters of two different three-band Hubbard models are obtained using the LDA and the downfolding Nth-order muffin-tin orbital technique with N=0 and 1 respectively. QMC calculations on 4-site clusters show that the d-wave transition temperature Tc depends sensitively on the parameters. While the N=1 MTO basis set which reproduces all three $pd\sigma$ bands leads to a d-wave transition, the N=0 set which merely reproduces the LDA Fermi surface and velocities does not. 
P. R. C. Kent, T. Saha-Dasgupta, O. Jepsen, O. K. Andersen, A.   Macridin, T. A. Maier, M. Jarrell, T. C. Schulthess