N-Picoloylhydrazide (Hphz) and its binuclear palladium complex [Pd₂(phz)₂Cl₂] were synthesized and determined by single crystal X-ray diffraction. They belong to monoclinic system. Crystal data: Hphz(C₆H₇N₃O), space group C2/c, a＝1.9245(2) nm, b＝0.38927(2) nm, c＝1.8073(2) nm, b＝107.255(2)°, V＝1.2931(2) nm³, Z＝8, D_c＝1.409 Mg/m³, F(000)＝576, m(Mo Kα)＝0.102 mm^－1, 0.0541 for 1257 observed reflections [I≥σ(I)], wR＝0.1762, GOF＝1.124; [Pd₂(phz)₂Cl₂](C₁₂H₁₂Cl₂N₆O₂Pd₂), space group P2₁/c, a＝1.48274(9) nm, b＝1.44797(9) nm, c＝0.73951(5) nm, β＝92.719(3)°, V＝1.5860(2) nm³, Z＝4, D_c＝2.329 Mg/m³, F(000)＝1072, μ(Mo Kα)＝2.62 mm^－1, R＝0.0262 for 2937 observed reflections [I≥σ(I)], wR＝0.0555, GOF＝0.959. The palladium(II) ion of the complex [Pd₂(phz)₂Cl₂] is coordinated with two pyridine nitrogen atom and two diazine nitrogen atom, forming a distorted square geometry. Pd…Pd distance is 0.38111 nm in the complex. There is a one-dimensional chain structure through the intermolecular hydrogen bonds N—H…Cl in complex crystal. There are π-π interactions in the neighboring ligands. The ab initio calculation with Hartree-Fork method showed that there are interactions between Pd and Pd in the complex molecule and the neighboring molecule. ν(C＝O) and ν(C＝N) were shifted to lower frequencies and ν(C—N) was shifted to higher frequencies in IR spectra. The emission lines (l_ex＝310 nm) were shifted to higher frequencies in fluorescence spectra.

Key words: crystal structure, N-picoloylhydrazide, binuclear palladium complex