The energies of the 3da/, and 3da/, levels have been determined for palladium and 13 of its compounds. The measured energies are related t o electronegativity differences between the palladium and the ligand donor atoms except in those cases where the ligand is a ?r acceptor. Ligands which are K acceptors cause greater energy level shifts since they permit greater depletion of electronic charge from the palladium. The energies of the K(2s) and P(2p) levels measured for several complexes were found to be nearly constant. The energy of the Br(3ps/,) level was lowered somewhat when the bromine occupied a bridging position in PdBrZ. The observed shifts can be "explained" by a combination of electronegativity and ?r-bonding effects. T h e cobalt(II1) complex L' = [Co( (C~H~)ZP(CHZ)ZP(C~H;)Z}Z(CN)Z] + acts as positively charged ligand giving compounds of the stoichiometry M(L+)XI, where M = Mn(II), F e ( I I ) , Co(II), N i ( I I ) , or Zn(I1) and X = halogen or pseudohalogen.On the basis of their electronic and vibrational spectra, magnetic susceptibilities, and X-ray diffraction patterns, these compounds zre formulated as pseudotetrahedral zwitterion complexes in which the cobalt(II1) cation is bound to MX3moieties through the nitrogen atom of one cyanide group.

DiscussionThe chemistry and structural data for oxygencarrying (p-peroxo) cobalt-histidine complexes and related substances have been previously summarized. lo In the present work, we have characterized the first known p-superoxo-dicobalt ion containing histidine as ligands. The presence of this bridge is clearly indicated by both the optical spectrum (678-nm peak) and the epr characteristics.1°

Chemische Verschiebungen im 3d‐Niveau des Palladiums wurden für Pd‐Metall und 13 Pd‐Verbindungen gemessen.

Die chemischen Verschiebungen von Pt in K‐Komplexverbindungen mit vierund sechsfach koordiniertem Pt werden mit früher gemessenen chemischen Verschiebungen von Pd in entsprechenden Pd‐Komplexen verglichen.