Several crystal structures and a theoretical DFT structure of the important catalyst (BINAP)PdCl2 (BINAP: 2,2'-bis(diphenylphosphino)-1,1'-binaphthyl) have been determined. The conformational flexibilities of the BINAP backbone and of the phenyl rings do not seem to be coupled. Two novel parameter have been introduced that define the Pi-Pi stacking between the phenyl and biaryl rings in systems similar to the BINAP ligand, as well as the delta angle that is sensitive to the important interaction of the exchangeable ligands of the palladium with the equatorial phenyl rings of the BINAP. Furthermore, the calculated bite angle is 3 degrees larger than the experimentally determined bite angles. (C) 2012 Elsevier Ltd. All rights reserved.