Non-local coherent screening in the bandwidth controlled Ca1-xSrxVO3 series

We studied the electronic structure of the Ca1-xSrxVO3 series using a cluster model. Both the coherent and incoherent structures in photoemission correspond to well screened states. The coherent structure (3d1/u(C)) is mostly due to a non-local coherent screening, whereas the incoherent feature (3d1/u(L)) is mainly related to the ligand screening. The poorly screened state (3d0) forms the lower Hubbard band and appears deeper in energy. The increased distortion in the series decrease the V-O-V angle and thus the non-local transfer integral T*. This produces the observed transfer of spectral weight from the coherent to the incoherent structure. A further decrease of T* would eventually induce a bandwidth controlled metal-insulator transition.