Cross-type orbital ordering in the layered hybrid organic-inorganic compound (C6H5CH2CH2NH3)2CuCl4

We have studied the magnetic properties and the underlying type of orbital ordering in the layered hybrid organic-inorganic compound (C6H5CH2CH2NH3)2CuCl4 by using ac-magnetic susceptibility and polarization-dependent soft-x-ray absorption spectroscopy at the Cu-L2 and Cu-L3 edges. We have established that the compound has a long-range ferromagnetic ordering both in plane and out of plane and we found from the analysis of the absorption spectra that the orbital ordering of the Cu2+ holes involves the cross-type dx2−z2/dy2−z2 arrangement which is different from the dx2−y2 arrangement found in the parent compounds of the high-Tc cuprate superconductors.