The synthesis procedure of the coordination compound [NiCl2 PPh3 2] involves the reaction of nickel II chloride hexahydrate NiCl26H2O with triphenylphosphine PPh3 in an appropriate solvent, such as ethanol or methanol. Here is a general procedure for the synthesis:1. Dissolve an appropriate amount of NiCl26H2O e.g., 1 mmol in a minimum amount of ethanol or methanol in a round-bottom flask.2. Add an excess of triphenylphosphine PPh3 to the solution e.g., 2.2 mmol to ensure complete coordination.3. Stir the mixture at room temperature for several hours or until the reaction is complete. The solution should turn from green to a dark red or brown color, indicating the formation of [NiCl2 PPh3 2].4. Remove the solvent by evaporation or under reduced pressure to obtain the crude product as a dark red or brown solid.5. Recrystallize the crude product from a suitable solvent, such as dichloromethane/hexane or ethanol, to obtain pure [NiCl2 PPh3 2] as dark red or brown crystals.To determine the purity of the synthesized [NiCl2 PPh3 2], various spectroscopic techniques can be employed:1. Infrared IR spectroscopy: The IR spectrum of the compound should show characteristic bands for PPh3 ligands, such as P-C stretching vibrations around 1000-1100 cm-1 and aromatic C-H stretching vibrations around 3000-3100 cm-1. The absence of any unreacted starting material peaks will indicate the purity of the compound.2. Nuclear Magnetic Resonance NMR spectroscopy: The 1H NMR and 31P NMR spectra can provide information about the coordination environment of the ligands. In the 1H NMR spectrum, the aromatic protons of PPh3 should appear as multiplets around 7-8 ppm, while the 31P NMR spectrum should show a single peak for the coordinated PPh3 ligands. The absence of any unreacted starting material peaks will indicate the purity of the compound.3. UV-Visible UV-Vis spectroscopy: The UV-Vis spectrum of [NiCl2 PPh3 2] should show a characteristic absorption band around 450-500 nm, corresponding to the d-d transition of the Ni II ion. The absence of any unreacted starting material peaks will indicate the purity of the compound.4. Elemental analysis or Inductively Coupled Plasma ICP analysis can be used to determine the metal content and confirm the stoichiometry of the compound.5. Single-crystal X-ray diffraction XRD can be used to determine the crystal structure of the compound and confirm its purity and identity.